Publications
Division of Condensed Matter Science
Takigawa group
We have been performing nuclear magnetic resonance experiments on various quantum spin systems and strongly correlated
electron systems to explore novel quantum phases with exotic ordering and fluctuation phenomena. The major achievementsin the year 2020 include: (1) development of systematic methods to identify symmetries of ordered phases with electronic
multipoles from the angle dependence of the NMR Knight shift and their application to 111Cd-NMR measurements in the spinorbit coupled metallic pyrochlore compound Cd2Re2O7, (2) quantitative determination of magnetic-field-induced dipolar andoctupolar moments in the low-temperature ordered phases of the 5d double-perovskite oxide Ba2MgReO6 based on the 17O
NMR experiments. In this material, strong spin-orbit coupling combined with the cubic crystal field generates a quartet groundstate with Jeff = 3/2, providing ideal platform to explore multipolar order of t2g electron systems.
1.

*Field-Orientation Effect on Ferro-Quadrupole Order in PrTi Al : S. Kittaka, T. Taniguchi, K. Hattori, S. Nakamura,
2 20

T. Sakakibara, M. Takigawa, M. Tsujimoto, A. Sakai, Y. Matsumoto and S. Nakatsuji, J. Phys. Soc. Jpn. 89, 043701(1-4)(2020).

2.

Regular-triangle trimer and charge order preserving the Anderson condition in the pyrochlore structure of CsW2O6:
Y. Okamoto, H. Amano, N. Katayama, H. Sawa, K. Niki, R. Mitoka, H. Harima, T. Hasegawa, N. Ogita, Y. Tanaka,
M. Takigawa, Y. Yokoyama, K. Takehana, Y. Imanaka, Y. Nakamura, H. Kishida and K. Takenaka, Nat Commun 11,3144-1-8 (2020).

3.

*Pressure-induced phase transition in the J -J square lattice antiferromagnet RbMoOPO Cl: H. Takeda, T. Yamauchi,
1 2
4

4.

*PrTi Al における強四極子秩序変数の磁場によるスイッチング - 磁場に依存する四極子間相互作用について -: 谷口 貴紀 ,2 20

M. Takigawa, H. Ishikawa and Z. Hiroi, Phys. Rev. B 103, 104406 (2021).

服部 一匡 , 橘高 俊一郎 , 瀧川 仁 , 固体物理 55, 245-264 (2020).

Sakakibara group
We investigated the magnetic phase transitions of the cubic chiral magnet EuPtSi by means of high-precision magnetization measurements and established the magnetic phase diagrams. The incommensurate-commensurate transition in the helicalstate with a tiny change in the propagation vectors was detected exclusively by the magnetization along the [111] direction.
The transition temperature TN* shifted to lower temperature with increasing H // [111]. The ground-state magnetizations of
the helical state for H // [100] and [111] were examined at temperatures below 100 mK. We found evidence that the q vectors
pinned to the lattice at low fields were depinned by increasing fields above 10 kOe and gradually rotated towards the field directions. Metastable skyrmion phase can be created at 60 mK by slowly cooling in a field. We obtained the ground-state magnetization of the skyrmion lattice state, showing a sharp tilted plateau structure. The transitions from the skyrmion phase to theconical phase by changing fields were perfectly discontinuous at 60 mK possibly because of the supercooled dynamics.
1.

*105Pd NMR and NQR study of the cubic heavy fermion system Ce Pd Si : I. Jakovac, M. Horvatic, E. F. Schwier,
3 20 62.

*Field-Orientation Effect on Ferro-Quadrupole Order in PrTi Al : S. Kittaka, T. Taniguchi, K. Hattori, S. Nakamura,
2 20

3.

†*Heavy Fermion State of YbNi Si without Local Inversion Symmetry: S. Nakamura, K. Hyodo, Y. Matsumoto,2 3

4.

*Kitaev Spin Liquid Candidate Os Cl Comprised of Honeycomb Nano-Domains: K. Kataoka, D. Hirai, T. Yajima,x 3

A. Prokofiev, S. Paschen, H. Mitamura, T. Sakakibara and M. S. Grbic, J. Phys.: Condens. Matter 32, 245601(1-7)(2020).
T. Sakakibara, M. Takigawa, M. Tsujimoto, A. Sakai, Y. Matsumoto and S. Nakatsuji, J. Phys. Soc. Jpn. 89, 043701(1-4)(2020).

Y. Haga, H. Sato, S. Ueda, K. Mimura, K. Saiki, K. Iso, M. Yamashita, S. Kittaka, T. Sakakibara and S. Ohara, J. Phys.
Soc. Jpn. 89, 024705(1-5) (2020).
D. Nishio-Hamane, R. Ishii, K.-Y. Choi, D. Wulferding, P. Lemmens, S. Kittaka, T. Sakakibara, H. Ishikawa, A. Matsuo,
K. Kindo and Z. Hiroi, J. Phys. Soc. Jpn. 89, 114709(1-9) (2020).
* Joint research among groups within ISSP.

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5.

†*Emergent spin-1 Haldane gap and ferroelectricity in a frustrated spin- 1/2 ladder: H. Ueda, S. Onoda, Y. Yamaguchi,

6.

†Fully gapped superconductivity without sign reversal in the topological superconductor PbTaSe : Y. Sun, S. Kittaka,
2

T. Kimura, D. Yoshizawa, T. Morioka, M. Hagiwara, M. Hagihala, M. Soda, T. Masuda, T. Sakakibara, K. Tomiyasu,
S. Ohira-Kawamura, K. Nakajima, R. Kajimoto, M. Nakamura, Y. Inamura, N. Reynolds, M. Frontzek, J. S. White,
M. Hase and Y. Yasui, Phys. Rev. B 101, 140408(1-6) (2020).
T. Sakakibara, K. Machida, R. Sankar, X. Xu, N. Zhou, X. Xing, Z. Shi, S. Pyon and T. Tamegai, Phys. Rev. B 102,024517(1-7) (2020).

7.

†Magnetic properties of a spin-1/2 honeycomb lattice antiferromagnet: Y. Kono, T. Okabe, N. Uemoto, Y. Iwasaki,

8.

†Magnetic properties of a spin-2 antiferromagnet with metal-radical hybrid spins: Y. Iwasaki, T. Okabe, N. Uemoto,9.

†Synthesis and Magnetic Properties of M2+Ti4+ Substituted Ba

Y. Hosokoshi, S. Kittaka, T. Sakakibara and H. Yamaguchi, Phys. Rev. B 101, 014437(1-6) (2020).

Y. Kono, Y. Hosokoshi, S. Nakamura, S. Kittaka, T. Sakakibara, M. Hagiwara, T. Kawakami and H. Yamaguchi, Phys.
Rev. B 101, 174412(1-6) (2020).

12Fe28Ti15O84: N. Yasuda, S. Kittaka, Y. Kono, T. Sakakibara, K. Kakizaki and K. Kamishima, J. Magn. Soc. Jpn. 44, 2005R004(1-5) (2020).

10. *Magnetization and Thermal Expansion Properties of Quantum Spin Ice Candidate Pr2Zr2O7: N. Tang, A. Sakai,
K. Kimura, S. Nakamura, M. Fu, Y. Matsumoto, T. Sakakibara and S. Nakatsuji, JPS Conf. Proc. 30, 011090(1-6)(2020).
11. *Single Crystal Growth and Unique Electronic States of Cubic Chiral EuPtSi and Related Compounds: Y. Ônuki,
M. Kakihana, W. Iha, K. Nakaima, D. Aoki, A. Nakamura, F. Honda, M. Nakashima, Y. Amako, J. Gouchi, Y. Uwatoko,
S. Nakamura, T. Sakakibara, T. Takeuchi, Y. Haga, H. Ikeda, H. Harima, M. Hedo and T. Nakama, JPS Conf. Proc. 29,012001(1-9) (2020).
12. *Unique Skyrmion Phases and Conduction Electrons in Cubic Chiral Antiferromagnet EuPtSi and Related Compounds:
Y. Ônuki, M. Kakihana, W. Iha, K. Nakaima, D. Aoki, A. Nakamura, F. Honda, M. Nakashima, Y. Amako, J. Gouchi,
Y. Uwatoko, S. Nakamura, T. Sakakibara, T. Takeuchi, Y. Haga, H. Ikeda, H. Harima, M. Hedo and T. Nakama, JPS
Conf. Proc. 30, 011008(1-11) (2020).
13. *Improved accuracy in high-frequency AC transport measurements in pulsed high magnetic fields: H. Mitamura,
R. Watanuki, E. Kampert, T. Förster, A. Matsuo, T. Onimaru, N. Onozaki, Y. Amou, K. Wakiya, K. T. Matsumoto,I. Yamamoto, K. Suzuki, S. Zherlitsyn, J. Wosnitza, M. Tokunaga, K. Kindo and T. Sakakibara, Review of Scientific
Instruments 91, 125107/1-25 (2020).
14. Orientation of point nodes and nonunitary triplet pairing tuned by the easy-axis magnetization in UTe2: S. Kittaka,
Y. Shimizu, T. Sakakibara, A. Nakamura, D. Li, Y. Homma, F. Honda, D. Aoki and K. Machida, Phys. Rev. Research 2,
032014(R)(1-6) (2020).
15. †Evidence for nematic superconductivity of topological surface states in PbTaSe2: T. Le, Y. Sun, H.-K. Jin, L. Che,
L. Yin, J. Li, G. Pang, C. Xu, L. Zhao, S. Kittaka, T. Sakakibara, K. Machida, R. Sankar, H. Yuan, G. Chen, X. Xu,
S. Li, Y. Zhou and X. Lu, Science Bulletin 65, 1349-1355 (2020).
16. *PrTi2Al20 における強四極子秩序変数の磁場によるスイッチング - 磁場に依存する四極子間相互作用について -: 谷口 貴紀 ,服部 一匡 , 橘高 俊一郎 , 瀧川 仁 , 固体物理 55, 245-264 (2020).

Mori group
We have successfully developed and unveiled unprecedented functional properties for the molecular materials and systems.
The major achievements in 2020 are (1) to establish the molecular design strategy of anhydrous base-acid-type organic proton
conductors as an electrolyte of a fuel cell for medium temperatures, (2) to investigate the alkyl-chain-length effect of thetransistor properties for anthracene-based organic semiconductors, and (3) to develop the Zn complex with vapochromism
induced by intermolecular electron transfer coupled with hydrogen-bond formation.
1.

†Anhydrous Purely Organic Solid-State Proton Conductors: Effects of Molecular Dynamics on the Proton Conductivity

2.

水素科学の最前線、新学術領域研究「ハイドロジェノミクス」の挑戦―高速・局所移動水素と電子とのカップリングによる新発想デバイスの設計 : 森 初果 , まてりあ 60, 165-168 (2020).

3.

*A computational examination of the electric-field-induced proton transfer along the interface hydrogen bond betweenof Imidazolium Hydrogen Dicarboxylates: Y. Sunairi, S. Dekura, A. Ueda, T. Ida, M. Mizuno and H. Mori, J. Phys. Soc.
Jpn. 89, 051008 (2020).

proton donating and accepting self-assembled monolayers: Y. Kanematsu, H. S. Kato, S. Yoshimoto, A. Ueda,† Joint research with outside partners.

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S. Yamamoto, H. Mori, J. Yoshinobu, I. Matsuda and M. Tachikawa, Chem. Phys. Lett. 741, 137091 (2020).
4.

*Vapochromism induced by intermolecular electron transfer coupled with hydrogen-bond formation in zinc dithiolene

5.

* 水素を活かすセラミクス

6.

Effect of Alkyl Chain Length on Charge Transport Property of Anthracene-Based Organic Semiconductors: D. Zhang,
S. Yokomori, R. Kameyama, C. Zhao, A. Ueda, L. Zhang, R. Kumai, Y. Murakami, H. Meng and H. Mori, ACS Appl.
Mater. Interfaces 13, 989 (2021).

7.

Terahertz-field-induced polar charge order in electronic-type dielectrics: H. Yamakawa, T. Miyamoto, T. Morimoto,
N. Takamura, S. Liang, H. Yoshimochi, T. Terashige, N. Kida, M. Suda, H. M. Yamamoto, H. Mori, K. Miyagawa,K. Kanoda and H. Okamoto, Nat Commun 12, 953 (2021).

8.

*The Simplest Model for Doped Poly(3,4-ethylenedioxythiophene) (PEDOT): Single-crystalline EDOT Dimer Radical

9.

Modulation of the Electronic States and Magnetic Properties of Nickel Catecholdithiolene Complex by Oxidationcoupled Deprotonation: S. Yokomori, S. Dekura, A. Ueda, R. Kumai, Y. Murakami and H. Mori, J. Mater. Chem. C(2021), accepted for publication.

complex: T. Fujino, M. Kawamura, T. Ozaki and H. Mori, J. Mater. Chem. C 8, 14939-14947 (2020).

プロトンー電子カップル型分子性結晶および二分子膜における機能開拓 : 森 初果 , 加藤 浩之 ,藤野 智子 , 上田 顕 , 吉信 淳 , セラミックス 56, 88-91 (2021).

Cation Salts: R. Kameyama, T. Fujino, S. Dekura, M. Kawamura, T. Ozaki and H. Mori, Chem. Eur. J. 27, 6696 (2021).

Osada group
The nonlinear anomalous Hall effect (AHE) was realized in organic conductors for the first time. First, using interlayer
magnetotransport, we experimentally confirmed that the weak charge ordering (CO) state of a layered organic conductor
α-(BEDT-TTF)2I3 is a two-dimensional massive Dirac fermion (DF) state with a pair of tilted gapped Dirac cones with finite
Berry curvature dipole. Next, we showed that the nonlinear AHE is measurable in the current-carrying state of this massive DF
system, where the Berry curvature balance is broken between two Dirac cones due to non-equilibrium distribution. In addition,
we proposed the current-field-cooling technique, which enhances the formation of single type of CO domains in experiments. Finally, we performed the transport measurement of α-(BEDT-TTF)2I3 in the weak CO state at 1.25GPa, and extracted
nonlinear signal from current-reversed data. We successfully observed nonlinear AHE with estimated order and its rectifying
characteristics.
1.

Possible Current-Induced Phenomena and Domain Control in an Organic Dirac Fermion System with Weak Charge
Ordering: T. Osada and A. Kiswandhi, J. Phys. Soc. Jpn. 89, 103701/1-5 (2020).

2.

Experimental Confirmation of Massive Dirac Fermions in Weak Charge-Ordering State in α-(BEDT-TTF)2I3:
K. Yoshimura, M. Sato and T. Osada, J. Phys. Soc. Jpn. 90, 033701/1-5 (2021).

3.

Possible Nonlinear Anomalous Thermoelectric Effect in Organic Massive Dirac Fermion System: T. Osada andA. Kiswandhi, J. Phys. Soc. Jpn. 90, 053704/1-5 (2021).

4.

黒リン超薄膜の電子構造と物性 : 長田 俊人 ,「グラフェンから広がる二次元物質の新技術と応用」, 第 6 章 10 節 , 吾郷浩樹・
齋藤理一郎 , ( エヌ・ティー・エス , 東京 , 2020), 437-443.

Yamashita group
We have been studying (1) quantum criticality in heavy-fermion materials by ultralow temperature cryostat, (2) thermal-Hall
conductivity of exotic excitations in frustrated magnets and (3) a new technique for the study of strongly-correlated electron
systems. In this year, we have performed (1) developments of ultralow-temperature measurements of thermal expansion of
CeCoIn5 and resistivity of YbRh2Si2, (2) thermal-Hall measurements of Neel-type skyrmions in GaV4Se8, and (3) spintronic
superconductor in EuSn2As2.
1.

Thermal-transport studies of kagomé antiferromagnets: M. Yamashita, M. Akazawa, M. Shimozawa, T. Shibauchi,
Y. Matsuda, H. Ishikawa, T. Yajima, Z. Hiroi, M. Oda, H. Yoshida, H.-Y. Lee, J. H. Han and N. Kawashima, J. Phys.:
Condens. Matter 32, 074001 (2020).

2.

†*Heavy Fermion State of YbNi Si without Local Inversion Symmetry: S. Nakamura, K. Hyodo, Y. Matsumoto,2 3

3.

Presence and absence of itinerant gapless excitations in the quantum spin liquid candidate EtMe3Sb[Pd(dmit)2]2:
M. Yamashita, Y. Sato, T. Tominaga, Y. Kasahara, S. Kasahara, H. Cui, R. Kato, T. Shibauchi and Y. Matsuda, Phys.

Y. Haga, H. Sato, S. Ueda, K. Mimura, K. Saiki, K. Iso, M. Yamashita, S. Kittaka, T. Sakakibara and S. Ohara, J. Phys.
Soc. Jpn. 89, 024705(1-5) (2020).

* Joint research among groups within ISSP.

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Rev. B 101, 140407(R) (2020).
4.

*Sample dependence of half-integer quantized thermal Hall effect in the Kitaev spin-liquid candidate α-RuCl :3

5.

†Ultralow temperature NMR of CeCoIn : M. Yamashita, M. Tashiro, K. Saiki, S. Yamada, M. Akazawa, M. Shimozawa,
5

6.

ヘリウム危機の現状と今後の課題について（解説記事）: 山下 穣 , 固体物理 55, 215-223 (2020).

7.

*Thermal Hall Effects of Spins and Phonons in Kagome Antiferromagnet Cd-Kapellasite: M. Akazawa, M. Shimozawa,

M. Yamashita, J. Gouchi, Y. Uwatoko, N. Kurita and H. Tanaka, Phys. Rev. B 102, 220404(R) (2020).
T. Taniguchi, H. Takeda, M. Takigawa and H. Shishido, Phys. Rev. B 102, 165154 (2020).

S. Kittaka, T. Sakakibara, R. Okuma, Z. Hiroi, H.-Y. Lee, N. Kawashima, J. H. Han and M. Yamashita, Phys. Rev. X 10,041059 (2020).

8.

*Pressure-induced phase transition in the J -J square lattice antiferromagnet RbMoOPO Cl: H. Takeda, T. Yamauchi,
1 2
4

9.

*Strongly correlated superconductivity in a copper-based metal-organic framework with a perfect kagome lattice:

M. Takigawa, H. Ishikawa and Z. Hiroi, Phys. Rev. B 103, 104406 (2021).

T. Takenaka, K. Ishihara, M. Roppongi, Y. Miao, Y. Mizukami, T. Makita, J. Tsurumi, S. Watanabe, J. Takeya,
M. Yamashita, K. Torizuka, Y. Uwatoko, T. Sasaki, X. Huang, W. Xu, D. Zhu, N. Su, J. -G. Cheng, T. Shibauchi and
K. Hashimoto, Sci. Adv. 7, eabf3996(1-8) (2021).

Division of Condensed Matter Theory
Tsunetsugu group
We have studied several topics of strongly correlated systems and nonequilibrium phenomena. Concerning correlated systems,
we have investigated the dynamics of domain wall driven by external magnetic or electric field in multiferroic materials, andfound its dynamical instability to splitting. We have also reexamined phenomenological Ginzburg-Landau theory for CDW
in layered compounds and found new local minima in the free-energy landscape. As for nonequilibrium phenomena, we haveanalyzed various aspects of high-harmonic generation in solids, including the disorder effect, dynamical point-group symmetries, and relativistic dispersion relation of Dirac semimetals. Regarding periodically-driven (Floquet) systems, we haveproposed a new symmetry and derived a general expression for nonequilibrium steady states. In isolated many-body quantum
systems, we have investigated conserved quantities that work as dynamical obstructions and prevent ordinary thermalization.
Related to the two topics, we studied quantum quench dynamics of strongly correlated electrons in one dimension and found a
clogging phenomena where particle current stops but energy current flows.
1.

Generalized hydrodynamic approach to charge and energy currents in the one-dimensional Hubbard model: Y. Nozawa
and H. Tsunetsugu, Phys. Rev. B 101, 035121 (2020).

2.

*Efficient Terahertz Harmonic Generation with Coherent Acceleration of Electrons in the Dirac Semimetal Cd As :3 2

3.

Explicit Construction of Local Conserved Quantities in the XYZ Spin-1/2 Chain: Y. Nozawa and K. Fukai, Phys. Rev.
Lett. 125, 090602 (2020).

4.

Time Crystals Protected by Floquet Dynamical Symmetry in Hubbard Models: K. Chinzei and T. N. Ikeda, Phys. Rev.
Lett. 125, 060601 (2020).

5.

Multivalley Free Energy Landscape and the Origin of Stripe and Quasi-Stripe CDW Structures in Monolayer MX2
Compounds: K. Nakatsugawa, S. Tanda and T. N. Ikeda, Sci. Rep. 10, 1239 (2020).

6.

General description for nonequilibrium steady states in periodically driven dissipative quantum systems: T. N. Ikeda and
M. Sato, Science Advances 6, eabb4019 (2020).

7.

Disorder effects on the origin of high-order harmonic generation in solids: K. Chinzei and T. N. Ikeda, Phys. Rev.
Research 2, 013033 (2020).

8.

High-order nonlinear optical response of a twisted bilayer graphene: T. N. Ikeda, Phys. Rev. Research 2, 032015(R)(2020).

9.

Noncommutative generalized Gibbs ensemble in isolated integrable quantum systems: K. Fukai, Y. Nozawa,K. Kawahara and T. N. Ikeda, Phys. Rev. Research 2, 033403 (2020).

B. Cheng, N. Kanda, T. N. Ikeda, T. Matsuda, P. Xia, T. Schumann, S. Stemmer, J. Itatani, N. P. Armitage and R. Matsunaga, Phys. Rev. Lett. 124, 117402 (2020).

† Joint research with outside partners.

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10. Dynamics of Composite Domain Walls in Multiferroics in Magnetic Field and Their Instability: K. Kawahara and
H. Tsunetsugu, J. Phys. Soc. Jpn. 90, 014703 (2021).
11. Quadrupole Orders on the fcc Lattice: H. Tsunetsugu, T. Ishitobi and K. Hattori, J. Phys. Soc. Jpn. 90, 043701 (2021).
12. Generalized hydrodynamics study of the one-dimensional Hubbard model: Stationary clogging and proportionality ofspin, charge, and energy currents: Y. Nozawa and H. Tsunetsugu, Phys. Rev. B 103, 035130 (2021).

Kato group
The main research subject of Kato Lab. is transport properties in mesoscopic devices. We studied (1) optimization of pumping
power under adiabatic charge driving, (2) microscopic theory for spin Hall magnetoresistance, (3) Cooper-pair transport througha Josephson junction array, and (4) transport properties through a Kondo quantum dot.
1.

Geometrical Optimization of Pumping Power under Adiabatic Parameter Driving: M. Hasegawa and T. Kato, J. Phys.
Soc. Jpn. 89, 064706 (2020).

2.

Fano-Kondo resonance versus Kondo plateau in an Aharonov-Bohm ring with an embedded quantum dot: M. Eto and
R. Sakano, Phys. Rev. B 102, 245402 (2020).

3.

Field-induced SU(4) to SU(2) Kondo crossover in a half-filling nanotube dot: Spectral and finite-temperature properties:
Y. Teratani, R. Sakano, T. Hata, T. Arakawa, M. Ferrier, K. Kobayashi and A. Oguri, Phys. Rev. B 102, 165106 (2020).

4.

Microscopic theory of spin Hall magnetoresistance: T. Kato, Y. Ohnuma and M. Matsuo, Phys. Rev. B 102, 094437(2020).

5.

Fermi Liquid Theory for Nonlinear Transport through a Multilevel Anderson Impurity: Y. Teratani, R. Sakano andA. Oguri, Phys. Rev. Lett. 125, 216801 (2020).

6.

Cooper-Pair Tunneling in Small Josephson Junction Arrays Under Radio-Frequency Irradiation: G. M. Kanyolo,
K. Takeda, Y. Mizugaki, T. Kato and H. Shimada, J. Low Temp. Phys. 201, 269 (2020).

7.

Effects of Tunnel-coupling Asymmetries on Fermi-liquid Transport through an Anderson Impurity: K. Tsutsumi,
Y. Teratani, A. Oguri and R. Sakano, JPS conf. ser. 30, 011174(1-6) (2020).

8.

†*DSQSS: Discrete Space Quantum Systems Solver: Y. Motoyama, K. Yoshimi, A. Masaki-Kato, T. Kato and9.

非平衡状態にある近藤効果（その 2）近藤効果入門 1: 阪野 塁 , 小栗 章 , 固体物理 55, 47-54 (2020).

N. Kawashima, Computer Physics Communications 264, 107944 (2021).

Division of Nanoscale Science
Katsumoto group
We further advanced the study of flying qubits using spin-polarized quantum Hall edge states. In particular, we improved thebeam splitter that splits the electron beam into two channels, and increased the splitting probability from a few percent to 50%,and obtained a beam splitter equivalent to a half mirror in quantum optics. The interferometer using this showed high visibilityof over 70%. In the super-normal-super (SNS) junction, the decrease of the superconducting critical current with the positive
gate voltage has been unexplained. We have found the phenomenon can be interpreted as the decrease of quantum coherence in
the Andreev bound state by the in-plane voltage.
1.

Gate-controlled unitary operation on flying spin qubits in quantum Hall edge states: T. Shimizu, T. Nakamura, Y. Hashimoto, A. Endo and S. Katsumoto, Phys. Rev. B 102, 235302 (2020).

2.

†Optoelectronic properties of laser-beam-patterned few-layer lateral MoS Schottky junctions: Y. Nagamine, J. Sato,23.

*Extracting the Chiral Contribution to the Negative Longitudinal Magnetoresistance in Epitaxial Pr Ir O Thin Films:
2 2 7

4.

†Room-temperature quantum spin Hall phase in laser-patterned few-layer 1T'- MoS : N. Katsuragawa, M. Nishizawa,
2

Y. Qian, T. Inoue, T. Nakamura, S. Maruyama, S. Katsumoto and J. Haruyama, Appl. Phys. Lett. 117, 043101 (2020).

T. Ohtsuki, Z. Tian, A. Endo, M. Halim, S. Katsumoto, Y. Kohama, K. Kindo, M. Lippmaa and S. Nakatsuji, JPS Conf.
Proc. 30, 011181 (1-6) (2020).
T. Nakamura, T. Inoue, S. Pakdel, S. Maruyama, S. Katsumoto, J. J. Palacios and J. Haruyama, Commun Mater 1, 51* Joint research among groups within ISSP.

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(2020).
5.

薄膜材料の電気特性 : 勝本 信吾 , 「2020 年版薄膜作製応用ハンドブック」, 第 2 章 , 權田俊一 , (NTS 出版 , 東京 ,2020), 39-79.

Otani group
This year, we have studied the following topics: spin conversion behaviors in bulk, the interfaces and the surfaces, the magnonphonon or magnon-magnon coupling in ferromagnetic heterostructures, and antiferromagnetic spintronics. I summarize theremarkable achievements this year below. We have established a phenomenological model explaining the contributions ofbulk and interfacial spin relaxation. Our study of transverse magnetoresistance in magnetic heterostructure evidenced the spin
swapping at the Rashba interface. We have experimentally demonstrated the conversion of acoustically induced spin currents tothe charge current using a metal/oxide Rashba interface. This study has also shown significant enhancement of magnon-phonon
coupling using the Brag reflector cavity structure. Besides, our international collaboration showed a large nonlinear ferromagnetic resonance shift due to strong magnon-magnon coupling. We had another collaborative project on skyrmion strings thatclarified their detailed propagation dynamics. This year, there are two exciting breakthroughs; Electrical manipulation of a
topological antiferromagnetic state and Emergent electromagnetic induction in a helical-spin magnet, both of which appeared in
Nature magazine.
1.

Underlayer material dependent symmetric and asymmetric behavior of voltage-controlled magnetic anisotropy in
CoFeB films: B. Rana, K. Miura, H. Takahashi and Y. Otani, J. Phys.: Condens. Matter 32, 414002 (2020).

2.

Electric-field control of interfacial in-plane magnetic anisotropy in CoFeB/MgO junctions: A. Deka, B. Rana, R. Anami,
K. Miura, H. Takahashi, Y. Otani and Y. Fukuma, Phys. Rev. B 101, 174405 (2020).

3.

Large nonlinear ferromagnetic resonance shift and strong magnon-magnon coupling in Ni80Fe20 nanocross array:
K. Adhikari, S. Sahoo, A. K. Mondal, Y. Otani and A. Barman, Phys. Rev. B 101, 054406 (2020).

4.

Phenomenological model for the direct and inverse Edelstein effects: H. Isshiki, P. Muduli, J. Kim, K. Kondou andY. Otani, Phys. Rev. B 102, 184411 (2020).

5.

*Effect of sample size on anomalous Nernst effect in chiral antiferromagnetic Mn Sn devices: H. Narita, T. Higo,
3

6.

Enhancement of acoustic spin pumping by acoustic distributed Bragg reflector cavity: Y. Hwang, J. Puebla, M. Xu,
A. Lagarrigue, K. Kondou and Y. Otani, Appl. Phys. Lett. 116, 252404 (2020).

7.

Evidence for spin swapping from modulation of transverse resistance in magnetic heterostructures with Rashba interface: H. Kim, S. Karube, J. Borge, J. Kim, K. Kondou and Y. Otani, Appl. Phys. Lett. 116, 122403 (2020).

8.

*Magneto-optical Kerr effect in a non-collinear antiferromagnet Mn Ge: M. Wu, H. Isshiki, T. Chen, T. Higo, S. Nakat3

9.

*Electrical manipulation of a topological antiferromagnetic state: H. Tsai, T. Higo, K. Kondou, T. Nomoto, A. Sakai,

M. Ikhlas, S. Nakatsuji and Y. Otani, Appl. Phys. Lett. 116, 072404 (2020).

suji and Y. Otani, Appl. Phys. Lett. 116, 132408 (2020).

A. Kobayashi, T. Nakano, K. Yakushiji, R. Arita, S. Miwa, Y. Otani and S. Nakatsuji, Nature 580, 608-613 (2020).

10. Emergent electromagnetic induction in a helical-spin magnet: T. Yokouchi, F. Kagawa, M. Hirschberger, Y. Otani,
N. Nagaosa and Y. Tokura, Nature 586, 232 (2020).
11. *Chirality-induced effective magnetic field in a phthalocyanine molecule: S. Miwa, K. Kondou, S. Sakamoto,
A. Nihonyanagi, F. Araoka, Y. Otani and D. Miyajima, Appl. Phys. Express 13, 113001 (1-4) (Spotlights 2020) (2020).
12. Acoustic ferromagnetic resonance and spin pumping induced by surface acoustic waves: J. Puebla, M. Xu, B. Rana,
K. Yamamoto, S. Maekawa and Y. Otani, J. Phys. D: Appl. Phys. 53, 264002 (2020).
13. *Structural and magnetic properties of Mn3Ge films with Pt and Ru seed layers: A. Kobayashi, T. Higo, S. Nakatsuji and
Y. Otani, AIP Advances 10, 015225(1-6) (2020).
14. Nonlinear Control of Damping Constant by Electric Field in Ultrathin Ferromagnetic Films: B. Rana, C. A. Akosa,
K. Miura, H. Takahashi, G. Tatara and Y. Otani, Phys. Rev. Applied 14, 014037 (2020).
15. Nonreciprocal surface acoustic wave propagation via magneto-rotation coupling: M. Xu, K. Yamamoto, J. Puebla,
K. Baumgaertl, B. Rana, K. Miura, H. Takahashi, D. Grundler, S. Maekawa and Y. Otani, Sci. Adv. 6, eabb1724 (2020).
16. Voltage controlled on-demand magnonic nanochannels: S. Choudhury, A. K. Chaurasiya, A. K. Mondal, B. Rana,
K. Miura, H. Takahashi, Y. Otani and A. Barman, Sci. Adv. 6, eaba5457 (2020).

† Joint research with outside partners.

ISSP Activity Report 2020161

17. Phase boundary exchange coupling in the mixed magnetic phase regime of a Pd-doped FeRh epilayer: J. R. Massey,
K. Matsumoto, M. Strungaru, R. C. Temple, T. Higo, K. Kondou, R. F. L. Evans, G. Burnell, R. W. Chantrell, Y. Otani
and C. H. Marrows, Phys. Rev. Materials 4, 024403(1-11) (2020).
18. Propagation dynamics of spin excitations along skyrmion strings: S. Seki, M. Garst, J. Waizner, R. Takagi, N. D. Khanh,
Y. Okamura, K. Kondou, F. Kagawa, Y. Otani and Y. Tokura, Nat Commun 11, 256 (2020).
19. *Electrical nucleation, displacement, and detection of antiferromagnetic domain walls in the chiral antiferromagnet
Mn3Sn: S. Sugimoto, Y. Nakatani, Y. Yamane, M. Ikhlas, K. Kondou, M. Kimata, T. Tomita, S. Nakatsuji and Y. Otani,
Commun Phys 3, 111 (2020).
20. Creation of magnetic skyrmions by surface acoustic waves: T. Yokouchi, S. Sugimoto, B. Rana, S. Seki, N. Ogawa,S. Kasai and Y. Otani, Nat. Nanotechnol. 15, 361 (2020).
21. Spintronic devices for energy-efficient data storage and energy harvesting: J. Puebla, J. Kim, K. Kondou and Y. Otani,
Commun Mater 1, 24 (2020).
22. Nontrivial torque generation by orbital angular momentum injection in ferromagnetic-metal/Cu/Al2O3 trilayers: J. Kim,
D. Go, H. Tsai, D. Jo, K. Kondou, H.-W. Lee and Y. Otani, Phys. Rev. B 103, L020407 (2021).
23. *Domain structure and domain wall dynamics in topological chiral antiferromagnets from the viewpoint of magnetic
octupole: Y. Otani and T. Higo, Appl. Phys. Lett. 118, 040501 (2021).
24. *Omnidirectional Control of Large Electrical Output in a Topological Antiferromagnet: T. Higo, Y. Li, K. Kondou,
D. Qu, M. Ikhlas, R. Uesugi, D. Nishio-Hamane, C. L. Chien, Y. Otani and S. Nakatsuji, Adv. Funct. Mater. 31,
2008971-12 (2021).
25. *Spin-orbit torque switching of the antiferromagnetic state in polycrystalline Mn3Sn/Cu/heavy metal heterostructures:
H. Tsai, T. Higo, K. Kondou, A. Kobayashi, T. Nakano, K. Yakushiji, S. Miwa, Y. Otani and S. Nakatsuji, AIP Advances
11, 045110 (1-6) (2021).
26. Strain-induced Megahertz Oscillation and Stable Velocity of an Antiferromagnetic Domain Wall: F. Chen, X. Ge,
W. Luo, R. Xing, S. Liang, X. Yang, L. You, R. Xiong, Y. Otani and Y. Zhang, Phys. Rev. Applied 15, 014030 (2021).
27. *Fabrication of polycrystalline Weyl antiferromagnetic Mn3Sn thin films on various seed layers: T. Nakano, T. Higo,
A. Kobayashi, S. Miwa, S. Nakatsuji and K. Yakushiji, Phys. Rev. Materials 5, 054402 (1-9) (2021).
28. Nanochannels for spin-wave manipulation in Ni80Fe20 nanodot arrays: S. Sahoo, S. N. Panda, S. Barman, Y. Otani and
A. Barman, Journal of Magnetism and Magnetic Materials 522, 167550 (2021).
29. *Giant Effective Damping of Octupole Oscillation in an Antiferromagnetic Weyl Semimetal: S. Miwa, S. Iihama,
T. Nomoto, T. Tomita, T. Higo, M. Ikhlas, S. Sakamoto, Y. Otani, S. Mizukami, R. Arita and S. Nakatsuji, Small Science
1, 2000062 (1-8) (2021).
30. *Large Hall Signal due to Electrical Switching of an Antiferromagnetic Weyl Semimetal State: H. Tsai, T. Higo,
K. Kondou, S. Sakamoto, A. Kobayashi, T. Matsuo, S. Miwa, Y. Otani and S. Nakatsuji, Small Science 1, 2000025 (1-9)(2021).

Komori group
Distribution of local lattice distortion due to the hetero atomic overlayer is investigated using scanning tunnelingmicroscopy(STM) on the Cu(111) surface covered by hexagonal Fe2N atomic layer. We utilize the moiré pattern to reach ahigher spatial resolution than simple STM observations. The distortion can be greatly affected by the formation of atomic
impurities at the subsurface. Ultrathin films of L10-type FeNi are grown using nitrogen-surfactant epitaxy on the Cu(001)substrate. Well-ordered films with little intermixing among Cu, Fe and Ni atoms are realized by optimizing the substratetemperature during the Fe and Ni deposition and the post-annealing temperature. Their ferromagnetic properties are studied bysoft X-ray magnetic circular dichroism. An out-of-plane magnetocrystalline anisotropy is large enough for dominating the film
shape anisotropy. Electronic structure of 3~4-degree twisted bilayer graphene is investigated using angle-resolved photoemission spectroscopy with synchrotron light. The interface between the two graphene sheets of the present samples is made in ahigh vacuum. Owing to the strong interlayer interaction, significant band modifications including replica bands are observedat the energy near the Dirac point and crossing points of the Dirac bands. In particular, partial flat bands appear with changes
in the Dirac velocity, depending on the twist angles. The observed band structure is consistent with the result of tight-binding
calculations.
1.

†*Orbital Angular Momentum Induced Spin Polarization of 2D Metallic Bands: T. Kobayashi, Y. Nakata, K. Yaji,

T. Shishidou, D. Agterberg, S. Yoshizawa, F. Komori, S. Shin, M. Weinert, T. Uchihashi and K. Sakamoto, Phys. Rev.
* Joint research among groups within ISSP.

162

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Lett. 125, 176401, 1-6 (2020).
2.

Sensing surface lattice strain with Kondo resonance of single Co adatom: K. Iwata, T. Miyamachi, E. Minamitani and
F. Komori, Appl. Phys. Lett. 116, 051604, 1-4 (2020).

3.

†Twisted bilayer graphene fabricated by direct bonding in a high vacuum: H. Imamura, A. Visikovskiy, R. Uotani,

4.

*Edge-state correlation accelerates metal-insulator transition in topological semimetal nanofilms: S. Ito, M. Arita,

5.

†*Topological Surface State of Bi Se Modified by Adsorption of Organic Donor Molecule Tetrathianaphthacene:
2 3

6.

Realizing large out-of-plane magnetic anisotropy in L10 FeNi films grown by nitrogen-surfactant epitaxy on Cu(001):
K. Kawaguchi, T. Miyamachi, T. Iimori, Y. Takahashi, T. Hattori, T. Yokoyama, M. Kotsugi and F. Komori, Phys. Rev.
Materials 4, 054403, 1-7 (2020).

7.

*Fully spin-polarized bulk states in ferroelectric GeTe: J. Krempaský, M. Fanciulli, L. Nicolaï, J. Minár, H. Volfová,

8.

Hexagonal iron nitride monolayer on Cu(001): Zigzag-line-in-trough alignment: M. Yamada, K. Ienaga, Y. Takahashi,
T. Miyamachi and F. Komori, Surface Science 700, 121679, 1-9 (2020).

9.

Subatomic Distortion of Surface Monolayer Lattice Visualized by Moiré Pattern: T. Hattori, N. Kawamura, T. Iimori,T. Miyamachi and F. Komori, Nano Lett. 21, 2406-2411 (2021).

T. Kajiwara, H. Ando, T. Iimori, K. Iwata, T. Miyamachi, K. Nakatsuji, K. Mase, T. Shirasawa, F. Komori and
S. Tanaka, Appl. Phys. Express 13, 075004, 1-5 (2020).
J. Haruyama, B. Feng, W. -C. Chen, H. Namatame, M. Taniguchi, C. -M. Cheng, G. Bian, S. -J. Tang, T. -C. Chiang,
O. Sugino, F. Komori and I. Matsuda, Science Advances 6, eaaz5015 (7 pages) (2020).

T. Kitazawa, K. Yaji, K. Shimozawa, H. Kondo, T. Yamanaka, H. Yaguchi, Y. Ishida, K. Kuroda, A. Harasawa,T. Iwahashi, Y. Ouchi, F. Komori, S. Shin and K. Kanai, Adv. Mater. Interfaces 7, 2000524, 1-8 (2020).

O. Caha, V. V. Volobuev, J. Sánchez-Barriga, M. Gmitra, K. Yaji, K. Kuroda, S. Shin, F. Komori, G. Springholz andJ. Hugo Dil, Phys. Rev. Research 2, 013107,1-7 (2020).

10. †*Atomic-layer Rashba-type superconductor protected by dynamic spin-momentum locking: S. Yoshizawa,
T. Kobayashi, Y. Nakata, K. Yaji, K. Yokota, F. Komori, S. Shin, K. Sakamoto and T. Uchihashi, Nat Commun 12, 1462
(2021).
11. †Electronic structure of 3 degree-twisted bilayer graphene on 4H-SiC(0001): T. Iimori, A. Visikovskiy, H. Imamura,T. Miyamachi, M. Kitamura, K. Horiba, H. Kumigashira, K. Mase, K. Nakatsuji, S. Tanaka and F. Komori, Phys. Rev.
Material 5 (2021), in print.

Hasegawa group
We have investigated monolayer superconducting materials using low temperature scanning tunneling microscopy (STM). In
the case of two-dimensional superconductors, it has been known that the superconductivity is directly transformed into insulator
by introducing defects or applying magnetic field. Recent transport measurements on superconducting crystalline thin films,
however, revealed the presence of metallic phases during the super-insulator transitions. In order to elucidate the phenomena
we performed local superconducting gap measurements by STM on atomically-thin well-ordered Pb superconductors under
the perpendicular magnetic field. We observed the metallic phase and found by using vicinal substrates to introduce regularlyarranged steps as scatterers that the critical temperature is reduced but the superconducting gap remains the same. Analyzingthese peculiar microscopic features will provide a new scenario on the super-insulator transition. We are now developing a
new local method to probe spin dynamics of nano-size structures including single atoms/molecules by detecting electron/ferromagnetic resonances based on spin-polarized STM. We have introduced radio-frequency (RF) cables into the STM head andsuccessfully detected response of the RF irradiation in spin-polarized tunneling current. Using spin-polarized STM we havecharacterized magnetic properties of FeCo alloy island structures and found that the magnetoanisotropy can be significantly
reduced by the alloying. We plan to use the alloyed islands as a sample for the resonance detection.
1.

Numerical calculation of the potential distribution on the Si(111)-7 × 7 surface for scanning tunneling potentiometry:
M. Hamada, H.-H. Yang and Y. Hasegawa, Jpn. J. Appl. Phys. 59, SN1016 1-6 (2020).

2.

Si(111)-7×7 表面上の一次元欠陥における電気伝導評価 : 浜田 雅之 , 長谷川 幸雄 , 表面と真空 63, 431-436 (2020).

3.

Enhanced critical magnetic field for monoatomic-layer superconductor by Josephson junction steps: F. Oguro, Y. Sato,
K. Asakawa, M. Haze and Y. Hasegawa, Phys. Rev. B 103, 085416 1-7 (2021).

† Joint research with outside partners.

ISSP Activity Report 2020

163

Lippmaa group
We concluded the project on fabricating iridate pyrochlore thin films by solid-state epitaxy. The behavior of iridium and othernoble metals in the oxide thin film growth process was studied. In particular, the spontaneous phase separation of noble metals
was studied in perovskite and pyrochlore lattices. Several techniques were studied for controlling the sheet carrier density inoxide heterostructures with delta-doping layers. The SrTiO3 / LaTiO3 system was used in these experiments. A new sacrificial
buffer layer process was developed for fabricating strain-free free-standing oxide thin films.
1.

*Growth of Pr Ir O thin films using solid phase epitaxy: T. Ohtsuki, Z. Tian, M. Halim, S. Nakatsuji and M. Lippmaa,
2 2 7

2.

Noble metal clustering and nanopillar formation in an oxide matrix: M. Lippmaa, S. Kawasaki, R. Takahashi andT. Yamamoto, Jpn. J. Appl. Phys. 59, 010501 (1-9) (2020).

3.

Tuning the carrier density in SrTiO3/LaTiO3/SrTiO3 quantum wells: J. N. Lee, X. Hou, R. Takahashi and M. Lippmaa,
Appl. Phys. Lett. 116, 171601 (1-5) (2020).

4.

† 水溶性犠牲層を用いた単結晶薄膜分離技術 : 高橋 竜太 , リップ マーミック , セラミックデータブック 48, 71-75 (2020).

5.

*Extracting the Chiral Contribution to the Negative Longitudinal Magnetoresistance in Epitaxial Pr Ir O Thin Films:
2 2 7

6.

Sacrificial Water-Soluble BaO Layer for Fabricating Free-Standing Piezoelectric Membranes: R. Takahashi and
M. Lippmaa, ACS Appl. Mater. Interfaces 12, 25042-25049 (2020).

7.

Nanopillar composite electrodes for solar-driven water splitting: M. Lippmaa, S. Kawasaki, R. Takahashi andT. Yamamoto, MRS Bulletin 46, 142-151 (2021).

8.

*Observation and control of the weak topological insulator state in ZrTe : P. Zhang, R. Noguchi, K. Kuroda, C. Lin, K.
59.

†Realization of closed-loop optimization of epitaxial titanium nitride thin-film growth via machine learning: I. Ohkubo,
Z. Hou, J. N. Lee, T. Aizawa, M. Lippmaa, T. Chikyow, K. Tsuda and T. Mori, Mater. Today Phys. 16, 100296 (1-6)(2021).

J. Appl. Phys. 127, 035303 (1-9) (2020).

T. Ohtsuki, Z. Tian, A. Endo, M. Halim, S. Katsumoto, Y. Kohama, K. Kindo, M. Lippmaa and S. Nakatsuji, JPS Conf.
Proc. 30, 011181 (1-6) (2020).

Kawaguchi, K. Yaji, A. Harasawa, M. Lippmaa, S. Nie, H. Weng, V. Kandyba, A. Giampietri, A. Barinov, Q. Li, G. D.
Gu, S. Shin and T. Kondo, Nat. Commun. 12, 406 (2021).

Functional Materials Group
Yoshinobu group
We conducted several research projects in the fiscal year 2020: (1) The surface chemistry of hydrogen and formic acid on Cu
step surfaces and Pd-Cu single atom alloy model catalysts studied by SR-PES, IRAS, HREELS and TPD. (2) The adsorption
and desorption of CO2 on Pt(997) studied by TPD and SR-XPS. (3) The adsorption and desorption of CH4 on Pt(997) studied by
IRAS, TPD and SR-XPS. (4) In-situ SR-XPS study of CVD graphene on a Cu surface. (5) AP-XPS study of Pd deposited MoS2
under hydrogen pressure. (6) THz field induced second harmonic light modulation on Pt(111).
1.

*Emergence of nearly flat bands through a kagome lattice embedded in an epitaxial two-dimensional Ge layer with2.

*Formation of BN-covered silicene on ZrB /Si(111) by adsorption of NO and thermal processes: J. Yoshinobu,
2

3.

The roles of step-site and zinc in surface chemistry of formic acid on clean and Zn-modified Cu(111) and Cu(997)
surfaces studied by HR-XPS, TPD, and IRAS: Y. Shiozawa, T. Koitaya, K. Mukai, S. Yoshimoto and J. Yoshinobu,
J. Chem. Phys. 152, 044703 (2020).

4.

*A computational examination of the electric-field-induced proton transfer along the interface hydrogen bond between

5.

†*Atomistic-Level Description of GaN/Water Interface by a Combined Spectroscopic and First-Principles Computa-a bitriangular structure: A. Fleurence, C. -C. Lee, R. Friedlein, Y. Fukaya, S. Yoshimoto, K. Mukai, H. Yamane,
N. Kosugi, J. Yoshinobu, T. Ozaki and Y. Yamada-Takamura, Phys. Rev. B 102, 201102 (2020).

K. Mukai, H. Ueda, S. Yoshimoto, S. Shimizu, T. Koitaya, H. Noritake, C.-C. Lee, T. Ozaki, A. Fleurence, R. Friedlein
and Y. Yamada-Takamura, J. Chem. Phys. 153, 064702 (2020).

proton donating and accepting self-assembled monolayers: Y. Kanematsu, H. S. Kato, S. Yoshimoto, A. Ueda,
S. Yamamoto, H. Mori, J. Yoshinobu, I. Matsuda and M. Tachikawa, Chem. Phys. Lett. 741, 137091 (2020).

* Joint research among groups within ISSP.

164

ISSP Activity Report 2020

tional Approach: M. Sato, Y. Imazeki, T. Takeda, M. Kobayashi, S. Yamamoto, I. Matsuda, J. Yoshinobu, Y. Nakano and
M. Sugiyama, J. Phys. Chem. C 124, 12466 (2020).
6.

C–H Bond Activation of Methane through Electronic Interaction with Pd(110): T. Koitaya, A. Ishikawa, S. Yoshimotoand J. Yoshinobu, J. Phys. Chem. C 125, 1368 (2021).

7.

* 水素を活かすセラミクス

8.

Role of Intermolecular Interactions in the Catalytic Reaction of Formic Acid on Cu(111): A. Shiotari, S. E. M. Putra,
Y. Shiozawa, Y. Hamamoto, K. Inagaki, Y. Morikawa, Y. Sugimoto, J. Yoshinobu and I. Hamada, Small 2021, 2008010(2021).

9.

†*Structure and electronic structure of van der Waals interfaces at a Au(111) surface covered with a well-ordered

プロトンー電子カップル型分子性結晶および二分子膜における機能開拓 : 森 初果 , 加藤 浩之 ,藤野 智子 , 上田 顕 , 吉信 淳 , セラミックス 56, 88-91 (2021).

molecular layer of n-alkanes: H. Mizushima, H. Koike, K. Kuroda, K. Yaji, A. Harasawa, Y. Ishida, M. Nakayama,
K. Mase, K. Mukai, T. Kitazawa, T. Kondo, J. Yoshinobu, S. Shin and K. Kanai, Applied Surface Science 535, 147673(2021).

10. 2020 年版薄膜作製応用ハンドブック(p.883-p.888):（權田俊一監修）第 3 編第 2 章第 7 節「薄膜の表面・界面制御と信頼性」
吉信 淳 , (NTS, Tokyo, Japan, 2020).

Akiyama group
In 2020, which is the last year of our NEDO laser project started in 2018, we made development (fab-less production) andcharacterizations of gain-sitched 1030-1060 nm InGaAs laser diodes (LDs) for short seed-pulse generation below 10 ps, andindeed demonstrated 8 ps pulses generated directly from our developed LDs. We also studied multi-section LDs with strong
nonolinearity for short-pulse generation mechanism analysis. Our study in 2020 on novel solar cells included lead-halide
Perovskite solar cells, space-use multi-junction solar cells, and textured solar cells. Our study on bio- and chemical-physics has
been extended to new luciferin analogs and caged-luciferins.
1.

Accurate modeling of electron-hole binding in CuCl. I. Exciton states: S. V. Nair, J. Usukura and E. Tokunaga, Phys.
Rev. B 102, 075202 (2020).

2.

Accurate modeling of electron-hole binding in CuCl. II. Biexciton wavefunction: J. Usukura, S. V. Nair andE. Tokunaga, Phys. Rev. B 102, 075203 (2020).

3.

In situ wavelength tuning of quantum-dot single-photon sources integrated on a CMOS-processed silicon waveguide:
R. Katsumi, Y. Ota, A. Osada, T. Tajiri, T. Yamaguchi, M. Kakuda, S. Iwamoto, H. Akiyama and Y. Arakawa, Appl.
Phys. Lett. 116, 041103 (2020).

4.

*Quantum-mechanical hydration plays critical role in the stability of firefly oxyluciferin isomers: State-of-the-art calcu-

5.

Exciton Localization and Enhancement of the Exciton–LO Phonon Interaction in a CsPbBr3 Single Crystal: K. Shibata,J. Yan, Y. Hazama, S. Chen and H. Akiyama, J. Phys. Chem. C 124, 18257 (2020).

6.

Theoretical Study of the Wavelength Selection for the Photocleavage of Coumarin-caged D-luciferin: J. Usukura, M.
Hiyama, M. Kurata, Y. Hazama, X. Qiu, F. M. Winnik, H. Akiyama and N. Koga, Photochem Photobiol 96, 805-814(2020).

7.

Quantitative immunohistochemistry using an antibody-fused bioluminescent protein: K.-Y. Wang, C. Wu, S. Shimajiri,
H. Kubota, H. Akiyama and Y. Ohmiya, BioTechnique 64, 302-306 (2020).

8.

High performance single-mode vertical cavity surface emitting lasers based on CsPbBr3 nanocrystals with simplified
processing: C. Zhao, J. Tao, J. Tian, G. Weng, H. Liu, Y. Liu, J. Yan, S. Chen, Y. Pan, X. Hu, S. Chen, H. Akiyama and
J. Chu, Chemical Engineering Journal (online), 127660 (2020).

9.

Lasing operation in the CsPbBr3 perovskite micron hemisphere cavity grown by chemical vapor deposition:
H. Zhang, C. Zhao, S. Chen, J. Tian, J. Yan, G. Weng, X. Hu, J. Tao, Y. Pan, S. Chen, H. Akiyama and J. Chu, Chemical
Engineering Journal 389, 124395 (2020).

lations of the excited states: Y. Noguchi, M. Hiyama, M. Shiga, H. Akiyama and O. Sugino, J. Chem. Phys. 153, 201103(2020).

10. Absolute electroluminescence imaging with distributed circuit modeling: Excellent for solar-cell defect diagnosis:
J. Hong, Y. Wang, Y. Chen, X. Hu, G. Weng, S. Chen, H. Akiyama, Y. Zhang, B. Zhang and J. Chu, Prog Photovolt Res
Appl 28, 295 (2020).

† Joint research with outside partners.

ISSP Activity Report 2020165

11. Modeling and design for low-cost multijunction solar cell via light-trapping rear texture technique: Applied in InGaP/
GaAs/InGaAs triple junction: L. Zhu, Y. Hazama, A. Reddy, K. Watanabe, Y. Nakano, M. Sugiyama and H. Akiyama,
Prog Photovolt Res Appl 28, 251 (2020).
12. Practical target values of Shockley–Read–Hall recombination rates in state-of-the-art triple-junction solar cells forrealizing conversion efficiencies within 1% of the internal radiative limit: T. Nakamura, M. Imaizumi, H. Akiyama andY. Okada, Prog Photovolt Res Appl 28, 417 (2020).
13. Quantitative study of electron tunneling dynamics in asymmetric coupled InGaN/GaN quantum wells: G. Weng, Y. Liu,
S. Chen, T. Ito, X. Hu, C. Zhao, J. Liu, J. Chu and H. Akiyama, Applied Optics 59, 6231-6236 (2020).
14. Importance of Interfacial Passivation in the High Efficiency of Sb2Se3 Thin-Film Solar Cells: Numerical Evidence:
Y. Chen, Y. Wang, R. Wang, X. Hu, J. Tao, G.-E. Weng, C. Zhao, S. Chen, Z. Zhu, J. Chu and H. Akiyama, ACS Appl.
Energy Mater. 11, 10415–10422 (2020).
15. *Direct generation of sub-picosecond pulse via multi-section gain switching: T. Nakamura, T. Ito, H. Nakamae, C. Kim,
Y. Hazama, Y. Kobayashi, R. Kuroda and H. Akiyama, Opt. Lett. 46, 1277 (2021).
16. Fabricating over 7%-efficient Sb2(S,Se)3 thin-film solar cells by vapor transport deposition using Sb2Se3 and Sb2S3
mixed powders as the evaporation source: X. Hu, J. Tao, R. Wang, Y. Wang, Y. Pan, G. Weng, X. Luo, S. Chen, Z. Zhu,
J. Chu and H. Akiyama, Journal of Power Sources 493, 229737 (2021).
17. Superior single-mode lasing in a self-assembly CsPbX3 microcavity over an ultrawide pumping wavelength range:
G. Weng, J. Yan, S. Chen, C. Zhao, H. Zhang, J. Tian, Y. Liu, X. Hu, J. Tao, S. Chen, Z. Zhu, H. Akiyama and J. Chu,
Photon. Res. 9, 54 (2021).
18. Electron–Hole Plasma Lasing Dynamics in CsPbClmBr3-m Microplate Lasers: G. Weng, J. Tian, S. Chen, J. Yan,
H. Zhang, Y. Liu, C. Zhao, X. Hu, X. Luo, J. Tao, S. Chen, Z. Zhu, J. Chu and H. Akiyama, ACS Photonics 8, 787(2021).
19. Adaptive automatic solar cell defect detection and classification based on absolute electroluminescence imaging:
Y. Wang, L. Li, Y. Sun, J. Xu, Y. Jia, J. Hong, X. Hu, G. Weng, X. Luo, S. Chen, Z. Zhu, J. Chu and H. Akiyama, Energy
229, 120606 (2021).
20. Enhanced Magneto-Optical Kerr Effect of GaAs-Based P-N Junctions in the Terahertz Range: K. Miyagawa, M. Nagai,
M. Ashida, C. Kim and H. Akiyama, J Infrared Milli Terahz Waves 42, 325 (2021).

Sugino group
We have studied the density functional theory for molecules and condensed matters either in the ground state or in the excitedstates. We have also studies energy-materials such as lithium-ion battery, solid-state battery and fuel-cell and bio-materials suchas oxyluciferin of firefly. We have also contributed to get theoretical interpretation of experiments. All are based on the firstprinciples calculations.
1.

Hydrogen at Electrochemical Interfaces: O. Sugino, J. Phys. Soc. Jpn. 89, 051013 (2020).

2.

†Nuclear quantum effect for hydrogen adsorption on Pt(111): L. Yan, Y. Yamamoto, M. Shiga and O. Sugino, Phys. Rev.

3.

*Quantum-mechanical hydration plays critical role in the stability of firefly oxyluciferin isomers: State-of-the-art calcu-

4.

†Machine learning exchange-correlation potential in time-dependent density-functional theory: Y. Suzuki, R. Nagai and

5.

†Structural Variation in Carbonate Electrolytes by the Addition of Li Salts Studied by X-Ray Total Scattering:

6.

†Dopant arrangements in Y-doped BaZrO under processing conditions and their impact on proton conduction: a large3

7.

*Edge-state correlation accelerates metal-insulator transition in topological semimetal nanofilms: S. Ito, M. Arita,

B 101, 165414 (2020).

lations of the excited states: Y. Noguchi, M. Hiyama, M. Shiga, H. Akiyama and O. Sugino, J. Chem. Phys. 153, 201103(2020).
J. Haruyama, Phys. Rev. A 101, 050501 (2020).

K. Kimura, K. Hayashi, H. Kiuchi, M. Morita, J. Haruyama, M. Otani, H. Sakaebe, F. Fujisaki, K. Mori, M. Yonemura,Y. Takabayashi, T. Nakatani, S. Fujinami, T. Fukunaga and E. Matsubara, Phys. Status Solidi B 257, 2000100 (2020).
scale first-principles thermodynamics study: S. Kasamatsu, O. Sugino, T. Ogawa and A. Kuwabara, J. Mater. Chem.
A 8, 12674 (2020).
J. Haruyama, B. Feng, W. -C. Chen, H. Namatame, M. Taniguchi, C. -M. Cheng, G. Bian, S. -J. Tang, T. -C. Chiang,* Joint research among groups within ISSP.

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O. Sugino, F. Komori and I. Matsuda, Science Advances 6, eaaz5015 (7 pages) (2020).
8.

†Surface-state Coulomb repulsion accelerates a metal-insulator transition in topological semimetal nanofilms: S. Ito,9.

†Challenge of advanced low temperature fuel cells based on high degree of freedom of group 4 and 5 metal oxides:

M. Arita, J. Haruyama, B. Feng, W. -C. Chen, H. Namatame, M. Taniguchi, C. -M. Cheng, G. Bian, S. -J. Tang, T. -C.
Chiang, O. Sugino, F. Komori and I. Matsuda, Sci. Adv. 6, eaaz5015 (2020).

A. Ishihara, S. Tominaka, S. Mitsushima, H. Imai, O. Sugino and K.-I. Ota, Current Opinion in Electrochemistry 21,
234 (2020).

10. †Completing density functional theory by machine learning hidden messages from molecules: R. Nagai, R. Akashi and
O. Sugino, npj Comput Mater 6, 43 (2020).
11. †Comparative Study on Sulfide and Oxide Electrolyte Interfaces with Cathodes in All-Solid-State Battery via FirstPrinciples Calculations: Y. Okuno, J. Haruyama and Y. Tateyama, ACS Appl. Energy Mater. 3, 11061 (2020).
12. †First-Principles Calculation of Copper Oxide Superconductors That Supports the Kamimura-Suwa Model:
H. Kamimura, M. Araidai, K. Ishida, S. Matsuno, H. Sakata, K. Shiraishi, O. Sugino and J.-S. Tsai, Condensed Matter 5,
69 (2020).
13. †Ab initio construction of the energy density functional for electron systems with the functional-renormalization-groupaided density functional theory: T. Yokota and T. Naito, Phys. Rev. Research 3, L012015 (2021).
14. †Advances and challenges for experiment and theory for multi-electron multi-proton transfer at electrified solid-liquidinterfaces: K. Sakaushi, T. Komeda, S. Hammes-Schiffer, M. M. Melander and O. Sugino, Phys. Chem. Chem. Phys.
22, 19401-19442 (2021).

Oka group
The Oka group has constructed the theory for detecting Majorana modes in Kitaev's chiral spin liquid using STM setups. In
addition, we have done a collaboration with experimentalists on novel transport properties in layered metals, as well as an Highharmonics generation measurement in 3D Dirac materials.
1.

h/e oscillations in interlayer transport of delafossites: C. Putzke, M. D. Bachmann, P. McGuinness, E. Zhakina,
V. Sunko, M. Konczykowski, T. Oka, R. Moessner, A. Stern, M. König, S. Khim, A. P. Mackenzie and P. J. W. Moll,
Science 368, 1234 (2020).

2.

Non-perturbative terahertz high-harmonic generation in the three-dimensional Dirac semimetal Cd3As2: S. Kovalev, R.
M. Dantas, S. Germanskiy, J.-C. Deinert, B. Green, I. Ilyakov, N. Awari, M. Chen, M. Bawatna, J. Ling, F. Xiu, P. H.
van Loosdrecht, P. Surówka, T. Oka and Z. Wang, Nature communications 11, 1-6 (2020).

3.

Scanning Tunneling Microscopy as a Single Majorana Detector of Kitaev’s Chiral Spin Liquid: M. Udagawa, S. Takayoshi and T. Oka, Phys. Rev. Lett. 126, 127201 (2021).

Inoue group
In 2020, we revealed a new family of light-driven inward H+ pumping rhodopsin, schizorhodopsin (SzR), from Asgard archaea
and marine micro-organisms. The mechanism of SzR was investigated by laser flash photolysis and FTIR spectroscopy. As theresult, it was revealed that the H+ of the retinal is released to the cytoplasmic milieu without being trapped at any amino acidresidues in the protein. This is considerably different from that another inward H+ pumping rhodopsin, xenorhodopsin. Also,
we reported the role of a conserved tryptophan (Trp163) in the gating the mechanism of channelrhodopsin (C1C2). While themutation of this residue (C1C2 W163F) reduced the channel activity, the H+ pump activity was manifested.
1.

Excitonic Coupling Effect on the Circular Dichroism Spectrum of Sodium-Pumping Rhodopsin KR2: K. J. Fujimotoand K. Inoue, J. Chem. Phys. 153, 045101 (2020).

2.

Allosteric Communication to the Retinal Chromophore upon Ion Binding in a Light-driven Sodium Ion Pumping
Rhodopsin: A. Otomo, M. Mizuno, K. Inoue, H. Kandori and Y. Mizutani, Biochemistry 59, 520-529 (2020).

3.

Schizorhodopsins: A Novel Family of Rhodopsins from Asgard archaea that Function as Light-Driven Inward H+
Pumps: K. Inoue, S. P. Tsunoda, M. Singh, S. Tomida, S. Hososhima, M. Konno, R. Nakamura, H. Watanabe, P. -A.
Bulzu, H. L. Banciu, A. -S. Andrei, T. Uchihashi, R. Ghai, O. Béjà and H. Kandori, Sci. Adv. 6, eaaz2441 (2020).

4.

Infrared spectroscopic analysis on structural changes around the protonated Schiff base upon retinal isomerizationin light-driven sodium pump KR2: S. Tomida, S. Ito, T. Mato, Y. Furutani, K. Inoue and H. Kandori, Biochimica et† Joint research with outside partners.

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Biophysica Acta (BBA) - Bioenergetics 1861, 148190 (2020).
5.

Physical disuse contributes to widespread chronic mechanical hyperalgesia, tactile allodynia, and cold allodynia throughneurogenic inflammation and spino-parabrachio-amygdaloid pathway activation: Y. Ohmichi, M. Ohmichi, R. Tashima,
K. Osuka, K. Fukushige, D. Kanikowska, Y. Fukazawa, H. Yawo, M. Tsuda, M. Naito and T. Nakano, PAIN 161,
1808-1823 (2020).

6.

Gate-keeper of ion transport – a highly conserved helix-3 tryptophan in a channelrhodopsin chimera, C1C2/ChRWR:
Y. Nagasaka, S. Hososhima, N. Kubo, T. Nagata, H. Kandori, K. Inoue and H. Yawo, Biophys. Physicobiol. 17, 59-69(2020).

7.

Active Learning for Level Set Estimation under Input Uncertainty and Its Extensions: Y. Inatsu, M. Karasuyama,
K. Inoue and I. Takeuchi, Neural Computation 32, 2486-2531 (2020).

8.

Active Learning of Bayesian Linear Models with High-Dimensional Binary Features by Parameter Confidence-Region
Estimation: Y. Inatsu, M. Karasuyama, K. Inoue, H. Kandori and I. Takeuchi, Neural Computation 32, 1998-2031(2020).

9.

Crystal structure of schizorhodopsin reveals mechanism of inward proton pumping: A. Higuchi, W. Shihoya, M. Konno,
T. Ikuta, H. Kandori, K. Inoue and O. Nureki, Proc. Natl. Acad. Sci. USA 118, e2016328118 (2021).

10. Exploration of natural red-shifted rhodopsins using a machine learning-based Bayesian experimental design: K. Inoue,
M. Karasuyama, R. Nakamura, M. Konno, D. Yamada, K. Mannen, T. Nagata, Y. Inatsu, H. Yawo, K. Yura, O. Béjà,
H. Kandori and I. Takeuchi, Commun. Biol. 4, 362 (2021).
11. TAT Rhodopsin Is an Ultraviolet-Dependent Environmental pH Sensor: C. Kataoka, T. Sugimoto, S. Shigemura,
K. Katayama, S. P. Tsunoda, K. Inoue, O. Béjà and H. Kandori, Biochemistry, acs.biochem.0c00951 (2021), in print.
12. 光で細胞を制御する―多様な微生物型ロドプシンとオプトジェネティクス―: 井上 圭一 , 光学 49, 2-7 (2020).
13. Shining light on rhodopsin selectivity: How do proteins decide whether to transport H+ or Cl–?: K. Inoue, J. Biol. Chem.
295, 14805-14806 (2020).
14. 光駆動タンパク質ロドプシンの分子機能エンジニアリング : 井上 圭一 , 生物工学会誌 98, 664-668 (2020).
15. ラットを用いたオプトジェネティクス（光遺伝学）: 八尾 寛 , 深澤 有吾 , 冨田 浩史 , 五十嵐 敬幸 , 日本実験動物協会情報
誌 LABIO 21 80, 5-8 (2020).
16. A series of commentaries for a symposium entitled “Session 3SDA - Optogenetics: applying photoreceptor for understanding biological phenomena”: S. P. Tsunoda and K. Inoue, Biophys Rev 12, 295 (2020).
17. Expanding horizons of biosciences by light-control: M. Kataoka and T. Nagata, Biophysics and Physicobiology (2021),
accepted for publication.
18. Application of Optogenetics for Muscle Cells and Stem Cells: T. Asano, D. B. L. Teh and H. Yawo, in: Optogenetics,
edited by Hiromu Yawo, Hideki Kandori, Amane Koizumi, Ryoichiro Kageyama, (Springer Nature, 2021), 359-375.
19. Diversity, Mechanism, and Optogenetic Application of Light-Driven Ion Pump Rhodopsins: K. Inoue, in: Optogenetics,
edited by Hiromu Yawo, Hideki Kandori, Amane Koizumi, Ryoichiro Kageyama, (Springer Nature, 2021), 89-126.
20. ロドプシンが拓くタンパク質科学の地平 : 井上 圭一 ,「未来探究２０５０ 東大 30 人の知性が読み解く世界」, 東京大学未来ビジョン研究センター , ( 日本経済新聞出版 , 2021), 74-83.

Quantum Materials Group
Oshikawa group
We conducted theoretical studies on a wide range of subjects in quantum many-body problem. In particular, we proposed anovel mechanism of producing robust flat band in a network of conducting segments. In particular, in a honeycomb network,
the flat band is stable as long as the hopping range is shorter than the segment length and the reflection symmetry of the honeycomb structure is kept. This may be realized in the nearly-commensurate charge density wave (NCCDW) phase of 1T-TaS2,
and could be a factor for the superconductivity observed at low temperatures in the vicinity of the NCCDW phase. We also
introduced a new argument based on tilted boundary conditions for the Lieb-Schultz-Mattis (LSM) ingappability. It removes theneed of an artificial restriction on system sizes, and elucidates the relation between the LSM ingappability in higher dimensions* Joint research among groups within ISSP.

168

ISSP Activity Report 2020and the anomaly in quantum field theory in 1+1 dimensions.
1.

†*Particle-Hole Symmetry Breaking in a Spin-Dimer System TlCuCl Observed at 100 T: X. -G. Zhou, Y. Yao, Y. H.
3

2.

†Stable Flatbands, Topology, and Superconductivity of Magic Honeycomb Networks: J. M. Lee, C. Geng, J. W. Park, M.

3.

Generalized Boundary Condition Applied to Lieb-Schultz-Mattis-Type Ingappabilities and Many-Body Chern Numbers:
Y. Yao and M. Oshikawa, Phys. Rev. X 10, 031008 (2020).

4.

†Refined symmetry indicators for topological superconductors in all space groups: S. Ono, H. C. Po and H. Watanabe,

5.

†Filling-enforced constraint on the quantized Hall conductivity on a periodic lattice: Y.-M. Lu, Y. Ran and M. Oshikawa,

6.

†Proof of the Absence of Long-Range Temporal Orders in Gibbs States: H. Watanabe, M. Oshikawa and T. Koma, J Stat
Phys 178, 926 (2020).

7.

Non-local order parameters and quantum entanglement for fermionic topological field theories: K. Inamura,
R. Kobayashi and S. Ryu, Journal of High Energy Physics 01, 121(1-30) (2020).

8.

Cyclotron resonance in Kondo insulator: Y. Tada, Physical Review Research 2, 023194 (2020).

9.

Quantum criticality of magnetic catalysis in two-dimensional correlated Dirac fermions: Y. Tada, Physical Review
Research 2, 033363 (2020).

Matsuda, A. Ikeda, A. Matsuo, K. Kindo and H. Tanaka, Phys. Rev. Lett. 125, 267207 1-6 (2020).
Oshikawa, S.-S. Lee, H. W. Yeom and G. Y. Cho, Phys. Rev. Lett. 124, 137002 (2020).

Sci. Adv. 6, eaaz8367 (1-14) (2020).

Annals of Physics 413, 168060 (2020).

10. Quantum valence bond ice theory for proton-driven quantum spin-dipole liquids: M. G. Yamada and Y. Tada, PhysicalReview Research 2, 043077 (2020).
11. †Higher anomalies, higher symmetries, and cobordisms II: Lorentz symmetry extension and enriched bosonic / fermionic quantum gauge theory: Z. Wan, J. Wang and Y. Zheng, Annals of Mathematical Sciences and Applications 5, 171(2020).
12. †Non-Fermi Liquids in Conducting Two-Dimensional Networks: J. M. Lee, M. Oshikawa and G. Y. Cho, Phys. Rev.
Lett. 126, 186601 (2021).
13. †Parafermionization, bosonization, and critical parafermionic theories: Y. Yao and A. Furusaki, J. High Energ. Phys.
2021, 285 (2021).
14. †Twisted boundary condition and Lieb-Schultz-Mattis ingappability for discrete symmetries: Y. Yao and M. Oshikawa,Phys. Rev. Lett. (2021), accepted for publication.

Nakatsuji group
A new era in quantum materials research arises, featuring discoveries of novel topological phases of matter and emergent quasiparticle excitations behaving as elusive elementary particles. Our research activities focus on designing and synthesizing newmaterials with emergent quantum properties that have never been seen before, then exploring the physics behind such properties with our world-leading measurement facilities. We aim to lead the innovative quest for new quantum materials that bear a
far-reaching impact not only on basic science but also on our everyday life in the future. Major research themes: 1. Solid-stateanalogs of relativistic particles and new quantum phenomena · Weyl fermion and chiral anomaly · Quantum spin ice, magnetic
monopole, and emergent photon 2. Room-temperature quantum transport phenomena in topological magnetic materials · Weyl
antiferromagnets and their application to spintronic devices · Giant thermal and optical responses driven by the Berry curvature
3. Quantum phase transition in strongly correlated systems · Non-Fermi-liquid behavior and exotic superconductivity in multipolar Kondo materials
1.

*Field-Orientation Effect on Ferro-Quadrupole Order in PrTi Al : S. Kittaka, T. Taniguchi, K. Hattori, S. Nakamura,
2 20

2.

Unveiling Quadrupolar Kondo Effect in the Heavy Fermion Superconductor PrV2Al20: M. Fu, A. Sakai, N. Sogabe,
M. Tsujimoto, Y. Matsumoto and S. Nakatsuji, J. Phys. Soc. Jpn. 89, 013704 (2020).

3.

*Growth of Pr Ir O thin films using solid phase epitaxy: T. Ohtsuki, Z. Tian, M. Halim, S. Nakatsuji and M. Lippmaa,
2 2 7

T. Sakakibara, M. Takigawa, M. Tsujimoto, A. Sakai, Y. Matsumoto and S. Nakatsuji, J. Phys. Soc. Jpn. 89, 043701(1-4)(2020).

J. Appl. Phys. 127, 035303 (1-9) (2020).

† Joint research with outside partners.

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4.

Anomalous transverse response of Co2MnGa and universality of the room-temperature ratio αijA/σijA across topologic
al magnets: L. Xu, X. Li, L. Ding, T. Chen, A. Sakai, B. Fauqué, S. Nakatsuji, Z. Zhu and K. Behnia, Phys. Rev. B 101,
180404 (2020).

5.

Antichiral spin order, its soft modes, and their hybridization with phonons in the topological semimetal Mn3Ge:
Y. Chen, J. Gaudet, S. Dasgupta, G. G. Marcus, J. Lin, T. Chen, T. Tomita, M. Ikhlas, Y. Zhao, W. C. Chen, M. B. Stone,
O. Tchernyshyov, S. Nakatsuji and C. Broholm, Phys. Rev. B 102, 054403 (2020).

6.

Strong in-plane anisotropy in the electronic structure of fixed-valence β-LuAlB4: P. Reiss, J. Baglo, H. Tan, X. Chen,
S. Friedemann, K. Kuga, F. Malte Grosche, S. Nakatsuji and M. Sutherland, Phys. Rev. B 102, 081102 (2020).

7.

Impact of the lattice on magnetic properties and possible spin nematicity in the S = 1 triangular antiferromagnet
NiGa2S4: M. E. Valentine, T. Higo, Y. Nambu, D. Chaudhuri, J. Wen, C. Broholm, S. Nakatsuji and N. Drichko, Phys.
Rev. Lett. 125, 197201 (2020).

8.

Many-Body Resonance in a Correlated Topological Kagome Antiferromagnet: SS. Zhang, JX. Yin, M. Ikhlas, HJ. Tien,
R. Wang, N. Shumiya, GQ. Chang, SS. Tsirkin, YG. Shi, CJ. Yi, Z. Guguchia, H. Li, WH. Wang, TR. Chang, ZQ. Wang,
YF. Yang, T. Neupert, S. Nakatsuji and MZ. Hasan, Phys. Rev. Lett. 125, 046401 (2020).

9.

A tunable stress dilatometer and measurement of the thermal expansion under uniaxial stress of Mn3Sn: M. Ikhlas, K. R.
Shirer, P.-Y. Yang, A. P. Mackenzie, S. Nakatsuji and C. W. Hicks, Appl. Phys. Lett. 117, 233502 (2020).

10. *Effect of sample size on anomalous Nernst effect in chiral antiferromagnetic Mn3Sn devices: H. Narita, T. Higo,
M. Ikhlas, S. Nakatsuji and Y. Otani, Appl. Phys. Lett. 116, 072404 (2020).
11. *Magneto-optical Kerr effect in a non-collinear antiferromagnet Mn3Ge: M. Wu, H. Isshiki, T. Chen, T. Higo, S. Nakatsuji and Y. Otani, Appl. Phys. Lett. 116, 132408 (2020).
12. Superconducting properties of the ternary boride YRh4B4: J. Jatmika, H. Maruyama, M. S. Rahman, A. Sakai, S. Nakatsuji, A. Iyo and T. Ebihara, Supercond. Sci. Technol. 33, 125006 (2020).
13. *Electrical manipulation of a topological antiferromagnetic state: H. Tsai, T. Higo, K. Kondou, T. Nomoto, A. Sakai,
A. Kobayashi, T. Nakano, K. Yakushiji, R. Arita, S. Miwa, Y. Otani and S. Nakatsuji, Nature 580, 608-613 (2020).
14. *Iron-based binary ferromagnets for transverse thermoelectric conversion: A. Sakai, S. Minami, T. Koretsune, T. Chen,
T. Higo, Y. Wang, T. Nomoto, M. Hirayama, S. Miwa, D. Nishio-Hamane, F. Ishii, R. Arita and S. Nakatsuji, Nature
581, 53-57 (2020).
15. 硬 X 線光電子分光と基礎物性測定により明らかにした価数の量子臨界現象 : 久我 健太郎 , 松本 洋介 , 大川 万里生 , 中
辻 知 , 放射光 33, 1-8 (2020).
16. Magnetic and transport properties of amorphous, B2 and L21 Co2MnGa thin films: Z. Zhu, T. Higo, S. Nakatsuji and
Y. Otani, AIP Advances 10, 085020 (2020).
17. *Structural and magnetic properties of Mn3Ge films with Pt and Ru seed layers: A. Kobayashi, T. Higo, S. Nakatsuji and
Y. Otani, AIP Advances 10, 015225(1-6) (2020).
18. *Extracting the Chiral Contribution to the Negative Longitudinal Magnetoresistance in Epitaxial Pr2Ir2O7 Thin Films:
T. Ohtsuki, Z. Tian, A. Endo, M. Halim, S. Katsumoto, Y. Kohama, K. Kindo, M. Lippmaa and S. Nakatsuji, JPS Conf.
Proc. 30, 011181 (1-6) (2020).
19. *Magnetization and Thermal Expansion Properties of Quantum Spin Ice Candidate Pr2Zr2O7: N. Tang, A. Sakai,
K. Kimura, S. Nakamura, M. Fu, Y. Matsumoto, T. Sakakibara and S. Nakatsuji, JPS Conf. Proc. 30, 011090(1-6)(2020).
20. Large Nernst Effect and Thermodynamics Properties in Weyl Antiferromagnet: T. Tomita, M. Ikhlas and S. Nakatsuji,
JPS Conf. Proc 30, 011009/1-7 (2020).
21. *Room-temperature terahertz anomalous Hall effect in Weyl antiferromagnet Mn3Sn thin films: T. Matsuda, N. Kanda,
T. Higo, N. P. Armitage, S. Nakatsuji and R. Matsunaga, Nat Commun 11, 909 (2020).
22. *Electrical nucleation, displacement, and detection of antiferromagnetic domain walls in the chiral antiferromagnet
Mn3Sn: S. Sugimoto, Y. Nakatani, Y. Yamane, M. Ikhlas, K. Kondou, M. Kimata, T. Tomita, S. Nakatsuji and Y. Otani,
Commun Phys 3, 111 (2020).
23. Sample Quality Dependence of the Magnetic Properties in Non-Collinear Antiferromagnet Mn 3Sn: M. Ikhlas,
T. Tomita and S. Nakatsuji, JPS. Conf. Proc 30, 011177 (2020).

* Joint research among groups within ISSP.

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24. Crystal structure and magnetic properties of the ferromagnet CoMnSb: H. Nakamura, M. Y. P. Akbar, T. Tomita, A. A.
Nugroho and S. Nakatsuji, JPS Conference Proceedings 29, 013004/1-5 (2020).
25. Unconventional free charge in the correlated semimetal Nd2Ir2O7: K. Wang, B. Xu, C. W. Rischau, N. Bachar,
B. Michon, J. Teyssier, Y. Qiu, T. Ohtsuki, B. Cheng, N. P. Armitage, S. Nakatsuji and D. van der Marel, Nat. Phys. 16,
1194–1198 (2020).
26. Superconducting properties of the ternary boride YRh4B4: J. Jatmika, H. Maruyama, MS. Rahman, A. Sakai, S. Nakatsuji, A. Iyo and T. Ebihara, SUPERCONDUCTOR SCIENCE & TECHNOLOGY, 33, 125006 (2020).
27. *Low Gilbert damping in the nodal-line semimetal D03-Fe3Ga epitaxial thin film: S. Sakamoto, T. Higo, S. Tamaru,
H. Kubota, K. Yakushiji, S. Nakatsuji and S. Miwa, Phys. Rev. B 103, 165122 (1-5) (2021).
28. *Domain structure and domain wall dynamics in topological chiral antiferromagnets from the viewpoint of magnetic
octupole: Y. Otani and T. Higo, Appl. Phys. Lett. 118, 040501 (2021).
29. *Omnidirectional Control of Large Electrical Output in a Topological Antiferromagnet: T. Higo, Y. Li, K. Kondou,
D. Qu, M. Ikhlas, R. Uesugi, D. Nishio-Hamane, C. L. Chien, Y. Otani and S. Nakatsuji, Adv. Funct. Mater. 31,
2008971-12 (2021).
30. *Spin-orbit torque switching of the antiferromagnetic state in polycrystalline Mn3Sn/Cu/heavy metal heterostructures:
H. Tsai, T. Higo, K. Kondou, A. Kobayashi, T. Nakano, K. Yakushiji, S. Miwa, Y. Otani and S. Nakatsuji, AIP Advances
11, 045110 (1-6) (2021).
31. Anomalous transport due to Weyl fermions in the chiral antiferromagnets Mn3X, X=Sn, Ge: T. Chen, T. Tomita,
S. Minami, M. Fu, T. Koretsune, M. Kitatani, I. Muhammad, D. Nishio-Hamane, R. Ishii, F. Ishii, R. Arita and S. Nakatsuji, Nat. Commun. 12, 572 (2021).
32. Inhomogeneous Kondo-lattice in geometrically frustrated Pr2Ir2O7: M. Kavai, J. Friedman, K. Sherman, M. Gong,
I. Giannakis, S. Hajinazar, H. Hu, S. E. Grefe, J. Leshen, Q. Yang, S. Nakatsuji, A. N. Kolmogorov, Q. Si, M. Lawler
and P. Aynajian, Nat. Commun. 12, 1377 (2021).
33. *Fabrication of polycrystalline Weyl antiferromagnetic Mn3Sn thin films on various seed layers: T. Nakano, T. Higo,
A. Kobayashi, S. Miwa, S. Nakatsuji and K. Yakushiji, Phys. Rev. Materials 5, 054402 (1-9) (2021).
34. *Giant Effective Damping of Octupole Oscillation in an Antiferromagnetic Weyl Semimetal: S. Miwa, S. Iihama,
T. Nomoto, T. Tomita, T. Higo, M. Ikhlas, S. Sakamoto, Y. Otani, S. Mizukami, R. Arita and S. Nakatsuji, Small Science
1, 2000062 (1-8) (2021).
35. *Large Hall Signal due to Electrical Switching of an Antiferromagnetic Weyl Semimetal State: H. Tsai, T. Higo,
K. Kondou, S. Sakamoto, A. Kobayashi, T. Matsuo, S. Miwa, Y. Otani and S. Nakatsuji, Small Science 1, 2000025 (1-9)(2021).

Miwa group
We have studied the following topics this year: (1) Spin-torque effect on a chiral antiferromagnet Mn3Sn, (2) Thin film growthof a line-node ferromagnet Fe3X, and (3) Chiral molecular spintronics device. In topic (1), we find that it is feasible to control
a topological antiferromagnetic state in Mn3Sn by using an unconventional spin-transfer effect (Nature 580, 608). This is awork in collaboration with Nakatsuji and Otani groups. In topic (2), we have succeeded in preparing Fe3Al and Fe3Gd thin filmby using a molecular beam epitaxy method, which shows giant anomalous Nernst effect as those in a bulk form (Nature 581,
53). This is a work in collaboration with Nakatsuji group. In topic (3), we find a chirality-induced effective magnetic field in aphthalocyanine molecule at Fe/MgO interface. Unlike the previous study, our system shows an effective magnetic field in theabsence of a bias current in the system (Appl. Phys. Express 13, 113001, Spotlights 2020).
1.

Voltage-controlled magnetic anisotropy in an ultrathin nickel film studied by operando x-ray magnetic circulardichroism spectroscopy: R. Miyakaze, S. Sakamoto, T. Kawabe, T. Tsukahara, Y. Kotani, K. Toyoki, T. Nakamura,
M. Goto, Y. Suzuki and S. Miwa, Phys. Rev. B 102, 014419 (1-6) (2020).

2.

Investigation of gating effect in Si spin MOSFET: S. Lee, F. Rortais, R. Ohshima, Y. Ando, M. Goto, S. Miwa,
Y. Suzuki, H. Koike and M. Shiraishi, Appl. Phys. Lett. 116, 022403 (1-5) (2020).

3.

Sizable spin-transfer torque in the Bi/Ni80Fe20 bilayer film: M. Matsushima, S. Miwa, S. Sakamoto, T. Shinjo,
R. Ohshima, Y. Ando, Y. Fuseya and M. Shiraishi, Appl. Phys. Lett. 117, 042407 (1-4) (2020).

4.

*Electrical manipulation of a topological antiferromagnetic state: H. Tsai, T. Higo, K. Kondou, T. Nomoto, A. Sakai,

A. Kobayashi, T. Nakano, K. Yakushiji, R. Arita, S. Miwa, Y. Otani and S. Nakatsuji, Nature 580, 608-613 (2020).
† Joint research with outside partners.

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5.

*Iron-based binary ferromagnets for transverse thermoelectric conversion: A. Sakai, S. Minami, T. Koretsune, T. Chen,

T. Higo, Y. Wang, T. Nomoto, M. Hirayama, S. Miwa, D. Nishio-Hamane, F. Ishii, R. Arita and S. Nakatsuji, Nature
581, 53-57 (2020).

6.

Control of Spin–Orbit Torques by Interface Engineering in Topological Insulator Heterostructures: F. Bonell, M. Goto,
G. Sauthier, J. F. Sierra, A. I. Figueroa, M. V. Costache, S. Miwa, Y. Suzuki and S. O. Valenzuela, Nano Lett. 20,
5893-5899 (2020).

7.

Detection of Spin Transfer from Metal to Molecule by Magnetoresistance Measurement: H. Gamou, K. Shimose,
R. Enoki, E. Minamitani, A. Shiotari, Y. Kotani, K. Toyoki, T. Nakamura, Y. Sugimoto, M. Kohda, J. Nitta and S. Miwa,
Nano Lett. 20, 75-80 (2020).

8.

*Chirality-induced effective magnetic field in a phthalocyanine molecule: S. Miwa, K. Kondou, S. Sakamoto,

9.

Over 1% magnetoresistance ratio at room temperature in non-degenerate silicon-based lateral spin valves: H. Koike,
S. Lee, R. Ohshima, E. Shigematsu, M. Goto, S. Miwa, Y. Suzuki, T. Sasaki, Y. Ando and M. Shiraishi, Appl. Phys.
Express 13, 083002 (1-4) (2020).

A. Nihonyanagi, F. Araoka, Y. Otani and D. Miyajima, Appl. Phys. Express 13, 113001 (1-4) (Spotlights 2020) (2020).

10. Enhancement of spin signals by thermal annealing in silicon-based lateral spin valves: N. Yamashita, S. Lee,
R. Ohshima, E. Shigematsu, H. Koike, Y. Suzuki, S. Miwa, M. Goto, Y. Ando and M. Shiraishi, AIP Advances 10,095021 (1-6) (2020).
11. Electrical Control for Extending the Ramsey Spin Coherence Time of Ion-Implanted Nitrogen-Vacancy Centers inDiamond: S. Kobayashi, Y. Matsuzaki, H. Morishita, S. Miwa, Y. Suzuki, M. Fujiwara and N. Mizuochi, Phys. Rev.
Applied 14, 044033 (1-10) (2020).
12. Gate-Tunable Spin XOR Operation in a Silicon-Based Device at Room Temperature: R. Ishihara, Y. Ando, S. Lee,
R. Ohshima, M. Goto, S. Miwa, Y. Suzuki, H. Koike and M. Shiraishi, Phys. Rev. Applied 13, 044010 (1-9) (2020).
13. *Low Gilbert damping in the nodal-line semimetal D03-Fe3Ga epitaxial thin film: S. Sakamoto, T. Higo, S. Tamaru,
H. Kubota, K. Yakushiji, S. Nakatsuji and S. Miwa, Phys. Rev. B 103, 165122 (1-5) (2021).
14. Physically Unclonable Functions With Voltage-Controlled Magnetic Tunnel Junctions: Y. Tanaka, M. Goto, A. K.
Shukla, K. Yoshikawa, H. Nomura, S. Miwa, S. Tomishima and Y. Suzuki, IEEE Trans. Magn. 57, 3400806 (1-6)(2021).
15. *Spin-orbit torque switching of the antiferromagnetic state in polycrystalline Mn3Sn/Cu/heavy metal heterostructures:
H. Tsai, T. Higo, K. Kondou, A. Kobayashi, T. Nakano, K. Yakushiji, S. Miwa, Y. Otani and S. Nakatsuji, AIP Advances
11, 045110 (1-6) (2021).
16. *Fabrication of polycrystalline Weyl antiferromagnetic Mn3Sn thin films on various seed layers: T. Nakano, T. Higo,
A. Kobayashi, S. Miwa, S. Nakatsuji and K. Yakushiji, Phys. Rev. Materials 5, 054402 (1-9) (2021).
17. *Giant Effective Damping of Octupole Oscillation in an Antiferromagnetic Weyl Semimetal: S. Miwa, S. Iihama,
T. Nomoto, T. Tomita, T. Higo, M. Ikhlas, S. Sakamoto, Y. Otani, S. Mizukami, R. Arita and S. Nakatsuji, Small Science
1, 2000062 (1-8) (2021).
18. *Large Hall Signal due to Electrical Switching of an Antiferromagnetic Weyl Semimetal State: H. Tsai, T. Higo, K.
Kondou, S. Sakamoto, A. Kobayashi, T. Matsuo, S. Miwa, Y. Otani and S. Nakatsuji, Small Science 1, 2000025 (1-9)(2021).
19. 電圧トルク MRAM に向けた新材料探索と磁化反転制御技術開発 : 野崎 隆行 , 山本 竜也 , 三輪 真嗣 , 鈴木 義茂 , 湯浅
新治 , まぐね 15, 15-23 (2020).
20. 磁気抵抗効果を使ったスピントロニクス現象 : 三輪 真嗣 , 電気評論 105, 21-28 (2020).

Division of Data-Integrated Materials Science
Fukushima group
We have developed an automatic exhaustive calculation tool which is based on the Korriga-Kohn-Rostoker coherent potential approximation (KKR-CPA) method. Our tool can explore the huge materials space consisting of disordered systems andconstruct large-scale materials databases. In this year, we implemented new features in our tool. One is the scale-bridging* Joint research among groups within ISSP.

172

ISSP Activity Report 2020

(multi-scale) simulation technique combining KKR-CPA and Monte Carlo methods for magnetocaloric materials. We applied
this method to MnCoGe alloys systems and succeeded in quantitatively evaluating the Curie temperature, magnetic entropy,
and isothermal entropy. Another is the calculation technique of electronic structures, magnetic properties, and transport
properties at finite temperature. Temperature effects often have a significant influence on the materials properties. To investigate the electronic structures at finite temperature, we need to incorporate the effects of local phonon excitations and spinwave (magnon) excitations in the framework of the KKR-CPA method. In the KKR Green's function method, the single-sitet-matrix is the sum of the coefficients of partial wave expansion at each atomic position and contains information of the singlesite scattering effect. We can thus replace the multiple scattering effect by an effective medium potential using CPA. The
local phonon excitation and magnon excitation can be treated as as the configuration average with respect to the local phonon
displacements and local moment disorder (LMD) states, respectively. We performed KKR-CPA calculations of temperaturedependent electronic structures and transport properties of the half-metallic Heusler alloy Co2MnSi. The electrical resistivity
was calculated by the Kubo-Greenwood formula. For Co2MnSi, due to impurity scattering by the Mn-Co antisite disorder, arather large residual resistivity exists. Hundling the local phonon, magnon, and Mn-Co antisite disorders simultaneously by
CPA, we were able to reproduce the experimentally observed temperature-dependent resistivity. Thus, we not only calculated
the electronic structures incorporating temperature effects, which are difficult for conventional first-principles approaches,
but also estimated the transport properties of the half-metallic Heusler alloy. Our method replicated the experiments and wasdemonstrated to be effective. Applying this method to other Heusler alloys and superlattices with giant magnetoresistance(GMR) and TMR structures, it will be possible to exploit theoretically-driven materials design of next-generation spintronics.
1.

Hole-mediated ferromagnetism in a high-magnetic moment material, Gd-doped GaN: A. Masago, H. Shinya,
T. Fukushima, K. Sato and H. Katayama-Yoshida, J. Phys.: Condens. Matter 32, 485803(1-6) (2020).

2.

Magnetocaloric effect in MnCoGe alloys studied by first-principles calculations and Monte-Carlo simulation: H. B.
Tran, T. Fukushima, Y. Makino and T. Oguchi, Solid State Commun. 323, 114077(1-5) (2020).

3.

*First-principles calculations of finite temperature electronic structures and transport properties of Heusler alloy

4.

Tuning structural-transformation temperature toward giantmagnetocaloric effect in MnCoGe alloy: A theoretical study:
H. B. Tran, T. Fukushima, K. Sato, Y. Makino and T. Oguchi, J. Alloys Compd. 854, 157063(1-9) (2020).

5.

Spin injection through energy-band symmetry matching with high spin polarization in atomically controlled ferromagnet/ferromagnet/ semiconductor structures: M. Yamada, F. Kuroda, M. Tsukahara, S. Yamada, T. Fukushima,
K. Sawano, T. Oguchi and K. Hamaya, NPG Asia Mater. 12, 47(1-9) (2020).

6.

Valence states and the magnetism of Eu ions in Eu-doped GaN: T. Nunokawa, Y. Fujiwara, Y. Miyata, N. Fujimura,T. Sakurai, H. Ohta, A. Masago, H. Shinya, T. Fukushima, K. Sato and H. Katayama-Yoshida, J. Appl. Phys 127,083901(1-7) (2020).

7.

High Curie temperature in Eu-doped GaN caused by volume-compensated Ga-vacancy: A. Masago, H. Shinya,
T. Fukushima, K. Sato and H. Katayama-Yoshida, AIP Adv. 10, 025216(1-4) (2020).

8.

First-principles calculation of electronic density of states and Seebeck coefficient in transition-metal-doped Si–
Ge alloys: R. Yamada, A. Masago, T. Fukushima, H. Shinya, T. Q. Nguyen and K. Sato, Solid State Commun. 323,
110227(1-8) (2021).

9.

Effect of atomic configuration on magnetic properties and electronicstate of CoVMnAl quaternary heusler alloy:
R. Y. Umetsu, K. Saito, K. Ono, T. Fukushima, F. Kuroda, T. Oguchi and T. Ishigaki, J. Alloys Compd. 855,
157389(1-9) (2021).

Co2MnSi: H. Shinya, S. Kou, T. Fukushima, A. Masago, K. Sato, H. Katayama-Yoshida and H. Akai, Appl. Phys. Lett.
117, 042402(1-5) (2020).

10. Theoretical prediction of large anisotropic magnetocaloric effect in MnP: H. B. Tran, T. Fukushima, H. Momida,
K. Sato, Y. Makino and T. Oguchi, Comput. Mater. Sci. 188, 110227(1-8) (2021).
11. Intrinsic defect formation and the effect of transition metal doping on transport properties in a ductile thermoelectricmaterial α-Ag2S: a first-principles study: H. N. Nam, R. Yamada, H. Okumura, T. Q. Nguyen, K. Suzuki, H. Shinya,
A. Masago, T. Fukushima and K. Sato, Phys. Chem. Chem. Phys (2021), accepted for publication.

† Joint research with outside partners.

ISSP Activity Report 2020173

Materials Design and Characterization Laboratory
Hiroi group
A new titanium hydride complex BaCa2Ti2H14 with the 9-fold coordination was discovered. A new spin-orbit-coupled metal
candidate PbRe2O6 was studied. Kitaev spin liquid candidate OsxCl3 comprised of honeycomb nano-domains was investigated.
A multipolar order in the spin-orbit-coupled 5d Mott insulator B2MgReO6 was studied by high-resolution XRD.
1.

*Domain Control by Adjusting Anisotropic Stress in Pyrochlore Oxide Cd Re O : S. Tajima, D. Hirai, Y. Kinoshita,
2 2 7

2.

*Kitaev Spin Liquid Candidate Os Cl Comprised of Honeycomb Nano-Domains: K. Kataoka, D. Hirai, T. Yajima,x 3

3.

Variation in Superconducting Symmetry Against Pressure on Noncentrosymmetric Superconductor Cd2Re2O7
Revealed by 185/187Re Nuclear Quadrupole Resonance: S. Kitagawa, K. Ishida, T. C. Kobayashi, Y. Matsubayashi,
D. Hirai and Z. Hiroi, J. Phys. Soc. Jpn. 89, 053701 (2020).

4.

Anomalous changes of electric quadrupole order at low temperatures in the spin-orbit coupled metal Cd2Re2O7: S. Uji,
S. Sugiura, H. T. Hirose, T. Terashima, Y. Matsubayashi, D. Hirai, Z. Hiroi and T. Hasegawa, Phys. Rev. B 102, 155131(2020).

5.

Antiferromagnetic long-range order in the 5d(1) double-perovskite Sr2MgReO6: S. Gao, D. Hirai, H. Sagayama,
H. Ohsumi, Z. Hiroi and T.-H. Arima, Phys. Rev. B 101, 220412 (2020).

6.

Coexistence of odd-parity and even-parity order parameters in the multipole order phase of the spin-orbit coupled metal
Cd2Re2O7: Y. Matsubayashi, K. Sugii, D. Hirai, Z. Hiroi, T. Hasegawa, S. Sugiura, H. T. Hirose, T. Terashima andS. Uji, Phys. Rev. B 101, 205133 (2020).

7.

*Helicaland collinear spin density wave order in the S = 1/2 one-dimensional frustrated chain compound
NaCuMoO4(OH) investigated by neutron scattering: S. Asai, T. Oyama, K. Nawa, A. Nakao, K. Munakata,
K. Kuwahara, M. Hagihala, S. Itoh, Z. Hiroi and T. Masuda, Phys. Rev. B 101, 144437(1-8) (2020).

8.

*Zero-energy

9.

*Anisotropic Triangular Lattice Realized in Rhenium Oxychlorides A ReO Cl (A = Ba, Sr): D. Hirai, T. Yajima,3
5 2

M. Tokunaga, K. Akiba, T. C. Kobayashi, H. T. Hirose and Z. Hiroi, J. Phys. Soc. Jpn. 89, 114711 (2020).

D. Nishio-Hamane, R. Ishii, K.-Y. Choi, D. Wulferding, P. Lemmens, S. Kittaka, T. Sakakibara, H. Ishikawa, A. Matsuo,
K. Kindo and Z. Hiroi, J. Phys. Soc. Jpn. 89, 114709(1-9) (2020).

excitation in the classical kagome antiferromagnet NaBa2Mn3F11: S. Hayashida, H. Ishikawa,Y. Okamoto, T. Okubo, Z. Hiroi, G. J. Nilsen, H. Mutka and T. Masuda, Phys. Rev. B 101, 214409 (2020).
K. Nawa, M. Kawamura and Z. Hiroi, Inorg. Chem. 59, 10025 (2020).

10. Titanium Hydride Complex BaCa2Ti2H14 with 9-Fold Coordination: T. Yajima, H. Nakajima, T. Honda, K. Ikeda,
T. Otomo, H. Takeda and Z. Hiroi, Inorg. Chem. 59, 4228 (2020).
11. *Spin–orbit-coupled metal candidate PbRe2O6: S. Tajima, D. Hirai, T. Yajima, D. Nishio-Hamane, Y. Matsubayashi and
Z. Hiroi, Journal of Solid State Chemistry 288, 121359 (2020).
12. *Thermal Hall Effects of Spins and Phonons in Kagome Antiferromagnet Cd-Kapellasite: M. Akazawa, M. Shimozawa,
S. Kittaka, T. Sakakibara, R. Okuma, Z. Hiroi, H.-Y. Lee, N. Kawashima, J. H. Han and M. Yamashita, Phys. Rev. X 10,041059 (2020).
13. Detection of multipolar orders in the spin-orbit-coupled 5d Mott insulator B2MgReO6: D. Hirai, H. Sagayama, S. Gao,
H. Ohsumi, G. Chen, T.-H. Arima and Z. Hiroi, Phys. Rev. Research 2, 022063 (2020).
14. †*Single shot x-ray diffractometry in SACLA with pulsed magnetic fields up to 16 T: A. Ikeda, Y. H. Matsuda, X. Zhou,
T. Yajima, Y. Kubota, K. Tono and M. Yabashi, Phys. Rev. Research 2, 043175 1-6 (2020).
15. *Pressure-induced phase transition in the J1-J2 square lattice antiferromagnet RbMoOPO4Cl: H. Takeda, T. Yamauchi,
M. Takigawa, H. Ishikawa and Z. Hiroi, Phys. Rev. B 103, 104406 (2021).

Kawashima group
We developed highly efficient methods, algorithms, and parallelized programs based on the tensor network (TN) method andapplied them to relevant physical problems, which include the following: (1) development of decomposition method of a highranked tensor into a ring of smaller low-ranked tensors, (2) development of TN method for boundary phenomena, (3) study ofKitaev spin liquid by TN variational functions, (4) study of spin liquid in frustrated spin systems, (5) TN study of deconfinedcritical phenomena, and (6) TN implementation of rael-space renormalization group.
* Joint research among groups within ISSP.

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1.

Frustration-induced supersolid phases of extended Bose–Hubbard model in the hard-core limit: W.-L. Tu, H.-K. Wu and
T. Suzuki, J. Phys.: Condens. Matter 32, 455401 (2020).

2.

Tensor-Ring Decomposition with Index-Splitting: H.-Y. Lee and N. Kawashima, J. Phys. Soc. Jpn. 89, 054003(1-9)(2020).

3.

Abelian and non-Abelian chiral spin liquids in a compact tensor network: H.-Y. Lee, R. Kaneko, T. Okubo and
N. Kawashima, Phys. Rev. B 101, 035140 (2020).

4.

Boundary conformal spectrum and surface critical behavior of classical spin systems:A tensor network renormalization
study: S. Iino, S. Morita and N. Kawashima, Phys. Rev. B 101, 155418 (2020).

5.

Construction of variational matrix product states for the Heisenberg spin-1 chain: J. Kim, M. Kim, N. Kawashima, J. H.
Han and H.-Y. Lee, Phys. Rev. B 102, 085117(1-8) (2020).

6.

Competing quantum phases of hard-core bosons with tilted dipole-dipole interaction: H.-K. Wu and W.-L. Tu, Phys.
Rev. A 102, 053306 (2020).

7.

*Thermal Hall Effects of Spins and Phonons in Kagome Antiferromagnet Cd-Kapellasite: M. Akazawa, M. Shimozawa,
S. Kittaka, T. Sakakibara, R. Okuma, Z. Hiroi, H.-Y. Lee, N. Kawashima, J. H. Han and M. Yamashita, Phys. Rev. X 10,041059 (2020).

8.

Magnetic field induced quantum phases in a tensor network study of Kitaev magnets: H.-Y. Lee, R. Kaneko, L. E.
Chern, T. Okubo, Y. Yamaji, N. Kawashima and Y. B. Kim, Nature Communications 11, 1639 (2020).

9.

Magnetic field induced competing phases in spin-orbital entangled Kitaev magnets: L. E. Chern, R. Kaneko, H.-Y. Lee
and Y. B. Kim, Phys. Rev. Research 2, 013014 (2020).

10. Tensor network wave function of S=1 Kitaev spin liquids: H.-Y. Lee, N. Kawashima and Y. B. Kim, Phys. Rev.
Research 2, 033318(1-6) (2020).
11. * 分子動力学計算による複雑流体中のカルマン渦の解析 : 浅野 優太 , 渡辺 宙志 , 野口 博司 , 分子シミュレーション学会誌" アンサンブル " 22, 157-162 (2020).
12. Effective Ruderman–Kittel–Kasuya–Yosida-like Interaction in Diluted Double-exchange Model: Self-learning Monte
Carlo Approach: H. Kohshiro and Y. Nagai, J. Phys. Soc. Jpn. 90, 034711 (2021).
13. Continuous phase transition between Neel and valence bond solid phases in a J-Q-like spin ladder system: T. Ogino,
R. Kaneko, S. Morita, S. Furukawa and N. Kawashima, Phys. Rev. B 103, 085117 (2021).
14. Global optimization of tensor renormalization group using the corner transfer matrix: S. Morita and N. Kawashima,
Phys. Rev. B 103, 045131(1-6) (2021).
15. †*DSQSS: Discrete Space Quantum Systems Solver: Y. Motoyama, K. Yoshimi, A. Masaki-Kato, T. Kato and
N. Kawashima, Computer Physics Communications 264, 107944 (2021).
16. †*Kω— Open-source library for the shifted Krylov subspace method of the form (zI - H)x = b: T. Hoshi, M. Kawamura,
K. Yoshimi, Y. Motoyama, T. Misawa, Y. Yamaji, S. Todo, N. Kawashima and T. Sogabe, Computer Physics Communications 258, 107536 (2021).
17. "Data Assimilation Method for Experimental and First-Principles Data: Finite-Temperature Magnetization of(Nd,Pr,La,Ce)2(Fe,Co,Ni)14B": Y. Harashima, K. Tamai, S. Doi, M. Matsumoto, H. Akai, N. Kawashima, M. Ito,
N. Sakuma, A. Kato, T. Shoji and T. Miyake, Phys. Rev. Materials 5, 013806(1-10) (2021).
18. Scaling dimensions from linearized tensor renormalization group transformations: X. Lyu, R. G. Xu and N. Kawashima,
Phys. Rev. Research 3, 023048 (2021).
19. Boundary CFT and Tensor Network Approach to Surface Critical Phenomena of the Tricritical 3-State Potts model:
S. Iino, J Stat Phys 182, 56 (2021).
20. DSQSS: Discrete Space Quantum Systems Solver: Y. Motoyama, K. Yoshimi, A. Masaki-Kato, T. Kato and
N. Kawashima, Computer Physics Communications 264, 107944 (2021), accepted for publication.

Uwatoko group
The effect of pressure on the unique electronic state of the antiferromagnetic (AF) compound EuCu2Ge2 has been measured ina wide temperature range from 10 mK to 300 K by electrical resistivity measurements up to 10 GPa. The results exhibit that
† Joint research with outside partners.

ISSP Activity Report 2020

175

critical pressure, ~6.5 GPa, coincides with valence transition pressure, corresponding to the quantum criticality of the valencetransition. A “palm” cubic-anvil pressure cell (PCAC) having an outer diameter of 60 mm, the smallest cubic-anvil cell to date,
was fabricated to physical measurements with superconducting magnet. The PCAC is advantageous because a large sample
space and pressure homogeneity are secured even under frozen pressure media environment at high pressures. We investigate
the pressure effect on the large anomalous Hall effect (AHE) of Co3Sn2S2 up to 12 GPa with a palm cubic anvil cell apparatus
and first-principles calculations simulation. We find that both the ferromagnetic transition temperature and the AHE aresuppressed monotonically upon the application of high pressure. Combined with theoretical calculations, our results indicatethat the distance between Weyl points with opposite chirality in Co3Sn2S2 is substantially reduced accompanying the suppression of ferromagnetism by pressure, thus providing an experimental route to tune the AHE of magnetic Weyl semimetals via
modifying the nontrivial band topology.
1.

Pressure effect on the magnetoresistivity of topological semimetal RhSn: S. Xu, S. Xu, J. Sun, B. Wang, Y. Uwatoko,
T. Xia and J. Cheng, J. Phys.: Condens. Matter 32, 355601(1-6) (2020).

2.

Magnetoelectric Effect in the Antiferromagnetic Ordered State of Ce3TiBi5 with Ce Zig-Zag Chains: M. Shinozaki,
G. Motoyama, M. Tsubouchi, M. Sezaki, J. Gouchi, S. Nishigori, T. Mutou, A. Yamaguchi, K. Fujiwara, K. Miyoshi and
Y. Uwatoko, J. Phys. Soc. Jpn. 89, 033703(1-5) (2020).

3.

Quantum Criticality of Valence Transition for the Unique Electronic State of Antiferromagnetic Compound EuCu2Ge2:
J. Gouchi, K. Miyake, W. Iha, M. Hedo, T. Nakama, Y. Ônuki and Y. Uwatoko, J. Phys. Soc. Jpn. 89, 053703(1-5)(2020).

4.

Single-Crystal Growth and Physical Properties of EuZn2Ge2: M. Kosaka, S. Michimura, H. Hirabayashi, R. Numakura,
R. Iizuka, K. Kuwahara and Y. Uwatoko, J. Phys. Soc. Jpn. 89, 054704(1-8) (2020).

5.

Coupled magnetic and structural phase transitions in the antiferromagnetic polar metal Pb2CoOsO6 under pressure:
Y. Jiao, Y.-W. Fang, J. Sun, P. Shan, Z. Yu, H. L. Feng, B. Wang, H. Ma, Y. Uwatoko, K. Yamaura, Y. Guo, H. Chen and
J. Cheng, Phys. Rev. B 102, 144418(1-7) (2020).

6.

High pressure investigation of an organic three-dimensional Dirac semimetal candidate having a diamond lattice:
A. Kiswandhi, M. Maesato, S. Tomeno, Y. Yoshida, Y. Shimizu, P. Shahi, J. Gouchi, Y. Uwatoko, G. Saito and
H. Kitagawa, Phys. Rev. B 101, 245124(1-7) (2020).

7.

*Magnetotransport properties of tellurium under extreme conditions: K. Akiba, K. Kobayashi, T. C. Kobayashi,

8.

Physical properties and pressure-induced superconductivity in the single-crystalline band insulator SnO: S. Xu, Y. Zou,
J. Sun, Z. Liu, X. Yu, J. Gouchi, Y. Uwatoko, Z. G. Cheng, B. Wang and J. Cheng, Phys. Rev. B 101, 104501(1-8)(2020).

9.

Pressure-induced incommensurate antiferromagnetic order in a ferromagnetic B-site ordered double-perovskite
Lu2NiMnO6: N. Terada, C. V. Colin, N. Qureshi, T. C. Hansen, K. Matsubayashi, Y. Uwatoko and A. A. Belik, Phys.
Rev. B 102, 094412(1-9) (2020).

R. Koezuka, A. Miyake, J. Gouchi, Y. Uwatoko and M. Tokunaga, Phys. Rev. B 101, 245111(1-6) (2020).

10. *Sample dependence of half-integer quantized thermal Hall effect in the Kitaev spin-liquid candidate α-RuCl3:
M. Yamashita, J. Gouchi, Y. Uwatoko, N. Kurita and H. Tanaka, Phys. Rev. B 102, 220404(R) (2020).
11. Superconducting phase diagrams of S-doped 2H−TaSe2 under hydrostatic pressure: S. Xu, Z. Liu, P. Yang, K. Chen,
J. Sun, J. Dai, Y. Yin, F. Hong, X. Yu, M. Xue, J. Gouchi, Y. Uwatoko, B. Wang and J. Cheng, Phys. Rev. B 102,
184511(1-9) (2020).
12. Weak ferromagnetism and possible non-Fermi-liquid behavior in the itinerant electronic material Co3SnC: B. Wang,
Y. Uwatoko, J. Cheng and Y. Sun, Phys. Rev. B 102, 085153(1-9) (2020).
13. NMR study under pressure on the iron-based superconductor FeSe1-xSx (x = 0.12 and 0.23): Relationship between
nematicity and AF fluctuations: T. Kuwayama, K. Matsuura, Y. Mizukami, S. Kasahara, Y. Matsuda, T. Shibauchi,
Y. Uwatoko and N. Fujiwara, Mod. Phys. Lett. B 34, 2040048(1-6) (2020).
14. Effects of Substituted Elements on Spin Reorientation in Mn2-xFexSb1-ySny: K. Noguchi, Y. Mitsui, M. Hiroi, R. Y.
Umetsu, J. Gouchi, Y. Uwatoko and K. Koyama, Mater. Trans. 61, 1492-1495 (2020).
15. Magnetic Field Effect on Nitrogenation of Sm2Fe17: K. Koyama, M. Onoue, R. Kobayashi, Y. Mitsui, R. Y. Umetsu andY. Uwatoko, Mater. Trans. 61, 1487-1491 (2020).
16. Magnetic Measurements of Narrow-Gap Semiconductor FeSb2 under High Pressure: T. Deguchi, K. Matsubayashi,
Y. Uwatoko, T. Koyama, T. Kohara, H. Nakamura, Y. Mitsui and K. Koyama, Mater. Trans. 61, 1476(1-4) (2020).

* Joint research among groups within ISSP.

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17. New phenomena of photo-luminescence and persistent luminescence of a Eu2+ ,Tb3+ codoped Ca6BaP4O17 phosphor
under high hydrostatic pressure: H. Guo, T. Seto, T. Geng, B. Zou, G. Li, Y. Uwatoko, Z. Tang, Z. Li and Y. Wang,
Dalton Trans. 49, 8056-2059 (2020).
18. Resistive anisotropy of candidate excitonic insulator Ta2NiSe5 under pressure: H. Arima, Y. Naito, K. Kudo,
N. Katayama, H. Sawa, M. Nohara, Y. F. Lu, K. Kitagawa, H. Takagi, Y. Uwatoko and K. Matsubayashi, J. Phys.: Conf.
Ser. 1609, 012001(1-6) (2020).
19. Pressure-Driven Eu2+-Doped BaLi2Al2Si2N6 : A New Color Tunable Narrow-Band Emission Phosphor for Spectroscopy
and Pressure Sensor Applications: Y. Wang, T. Seto, K. Ishigaki, Y. Uwatoko, G. Xiao, B. Zou, G. Li, Z. Tang, Z. Li andY. Wang, Adv. Funct. Mater. 1, 2001384(1-10) (2020).
20. *Single Crystal Growth and Unique Electronic States of Cubic Chiral EuPtSi and Related Compounds: Y. Ônuki,
M. Kakihana, W. Iha, K. Nakaima, D. Aoki, A. Nakamura, F. Honda, M. Nakashima, Y. Amako, J. Gouchi, Y. Uwatoko,
S. Nakamura, T. Sakakibara, T. Takeuchi, Y. Haga, H. Ikeda, H. Harima, M. Hedo and T. Nakama, JPS Conf. Proc. 29,012001(1-9) (2020).
21. *Unique Skyrmion Phases and Conduction Electrons in Cubic Chiral Antiferromagnet EuPtSi and Related Compounds:
Y. Ônuki, M. Kakihana, W. Iha, K. Nakaima, D. Aoki, A. Nakamura, F. Honda, M. Nakashima, Y. Amako, J. Gouchi,
Y. Uwatoko, S. Nakamura, T. Sakakibara, T. Takeuchi, Y. Haga, H. Ikeda, H. Harima, M. Hedo and T. Nakama, JPS
Conf. Proc. 30, 011008(1-11) (2020).
22. Pressure-induced second high-Tc superconducting phase in the organic-ion-intercalated (CTA)0.3FeSe single crystal:J. P. Sun, M. Z. Shi, B. Lei, S. X. Xu, Y. Uwatoko, X. H. Chen and J. -G. Cheng, EPL 130, 67004(1-5) (2020).
23. Pressure effect on the anomalous Hall effect of ferromagnetic Weyl semimetal Co3Sn2S2: Z. Y. Liu, T. Zhang, S. X. Xu,
P. T. Yang, Q. Wang, H. C. Lei, Y. Sui, Y. Uwatoko, B. S. Wang, H. M. Weng, J. P. Sun and J. -G. Cheng, Phys. Rev.
Materials 4, 044203(1-9) (2020).
24. Fabrication and evaluation via nuclear quadrupole resonance of a palm cubic-anvil pressure cell: S. Nakagawa, J. Gochi,
T. Kuwayama, S. Nagasaki, T. Takahashi, J. Cheng, Y. Uwatoko and N. Fujiwara, Review of Scientific Instruments 91,
073907(1-7) (2020).
25. Heat treatment effect on the magnetic properties and martensitic transformations of MnCoGe: K. Noguchi,
R. Kobayashi, Y. Mitsui, R. Y. Umetsu, J. Gouchi, Y. Uwatoko and K. Koyama, Journal of Magnetism and Magnetic
Materials 499, 166199(1-5) (2020).
26. Magnetic field-induced nitridation of Sm2Fe17: M. Onoue, R. Kobayashi, Y. Mitsui, R. Y. Umetsu, Y. Uwatoko andK. Koyama, Journal of Alloys and Compounds 835, 155193(1-7) (2020).
27. Superconducting-Gap Anisotropy of Iron Pnictides Investigated via Combinatorial Microwave Measurements:
T. Okada, Y. Imai, K. Kitagawa, K. Matsubayashi, M. Nakajima, A. Iyo, Y. Uwatoko, H. Eisaki and A. Maeda, Sci Rep
10, 7064(1-7) (2020).
28. Quasi-one-dimensional magnetic interactions and conduction electrons in EuCu5 and EuAu5 with the characteristic
hexagonal structure: S. Matsuda, J. Ota, K. Nakaima, W. Iha, J. Gouchi, Y. Uwatoko, M. Nakashima, Y. Amako,
F. Honda, D. Aoki, A. Nakamura, T. Takeuchi, Y. Haga, H. Harima, M. Hedo, T. Nakama and Y. Ônuki, Philosophical
Magazine JAN 2020, 1-14 (2020).
29. Redetermination of the crystal structure of R5Si4(R= Pr, Nd) from single-crystal X-ray diffraction data: K. Yokota,
R. Watanuki, M. Nakashima, M. Uehara, J. Gouchi, Y. Uwatoko and I. Umehara, Acta Crystallogr E Cryst Commun 76,
510 (2020).
30. Pressure-Induced Metallization and Structural Phase Transition in the Quasi-One-Dimensional TlFeSe2: Z.-Y. Liu,
Q.-X. Dong, P.-F. Shan, Y.-Y. Wang, J.-H. Dai, R. Jana, K.-Y. Chen, J.-P. Sun, B.-S. Wang, X.-H. Yu, G.-T. Liu,
Y. Uwatoko, Y. Sui, H.-X. Yang, G.-F. Chen and J.-G. Cheng, Chinese Phys. Lett. 37, 047102 (2020).
31. Crystallographic and superconducting properties of filled skutterudite SrOs 4P12: Y. Kawamura, S. Deminami,
K. Takeda, T. Kuzuya, L. Salamakha, H. Michor, E. Bauer, J. Gouchi, Y. Uwatoko, T. Kawae and C. Sekine, Phys. Rev.
B 103, 085139(1-9) (2021).
32. *Strongly correlated superconductivity in a copper-based metal-organic framework with a perfect kagome lattice:
T. Takenaka, K. Ishihara, M. Roppongi, Y. Miao, Y. Mizukami, T. Makita, J. Tsurumi, S. Watanabe, J. Takeya,
M. Yamashita, K. Torizuka, Y. Uwatoko, T. Sasaki, X. Huang, W. Xu, D. Zhu, N. Su, J. -G. Cheng, T. Shibauchi and
K. Hashimoto, Sci. Adv. 7, eabf3996(1-8) (2021).
33. Author Correction: Experimental evidence for the existence of a second partially-ordered phase of ice VI: R. Yamane,† Joint research with outside partners.

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177

K. Komatsu, J. Gouchi, Y. Uwatoko, S. Machida, T. Hattori, H. Ito and H. Kagi, Nat Commun 12, 1800 (2021).
34. Experimental evidence for the existence of a second partially-ordered phase of ice VI: R. Yamane, K. Komatsu,
J. Gouchi, Y. Uwatoko, S. Machida, T. Hattori, H. Ito and H. Kagi, Nat Commun 12, 1129(1-6) (2021).
35. High-pressure phase diagrams of FeSe1-xTex: correlation between suppressed nematicity and enhanced superconductivity: K. Mukasa, K. Matsuura, M. Qiu, M. Saito, Y. Sugimura, K. Ishida, M. Otani, Y. Onishi, Y. Mizukami, K. Hashimoto, J. Gouchi, R. Kumai, Y. Uwatoko and T. Shibauchi, Nat Commun 12, 381(1-7) (2021).
36. Pressure induced superconducting state in ideal topological insulator BiSbTe3: V. K. Gangwar, S. Kumar, M. Singh,
L. Ghosh, Y. Zhang, P. Shahi, M. Muntwiler, S. Patil, K. Shimada, Y. Uwatoko, J. Sau, M. Kumar and S. Chatterjee,
Phys. Scr. 96, 055802(1-8) (2021).
37. Internal and External Pressure Effects on Superconductivity in FeTe xSe1-x (x = 0.46, 0.54) Single Crystals:
G. Lingannan, K. Ganesan, S. Mariappan, R. Sankar, Y. Uwatoko and S. Arumugam, J Supercond Nov Magn 34,
725-731 (2021).

Ozaki group
In FY2020, we studied two issues: one is an investigation to unveil structural trends of ternary transition metal nano-particles,
and the other is the first-principles calculation of superconducting transition temperature of elemental bulks. (1) As the firstissue, we performed first-principles calculations and Monte Carlo sampling to investigate the structures of ternary PdRuM(M = Pt, Rh, or Ir) nanoparticles (NPs) with respect to three different spherical shapes. The calculations show that the atomic
position is dominant in determining the stability of the ternary NPs. For bare ternary NPs, Pd and Ru atoms favor a location on
the vertex sites and the core, respectively, which can be understood by the surface energy of the corresponding slab models. For
single-crystalline NPs, the binary shell could be either a solid solution or a segregation alloy depending on composition andmorphology. However, polycrystalline Ih NPs only form segregated binary shells surrounding the Ru core. Such configurations
tend to minimize the surface lattice to gain more energy from the d orbital of the transition metals. In addition to the bare NPs,
we study the oxidized ternary NPs. The results show that the Ru atoms penetrate outwards from the core to the surface reducing
the oxidation formation energy. This work clearly demonstrates the structural trends of small ternary NPs, unveiling that thestructural trends can be understood by the surface formation energy and the interplay between adsorbent and adsorbing oxygen
atoms. (2) As the second issue, we performed systematic calculations to understand the applicability and limitation of Density
functional theory for superconductors (SCDFT), which is one of the first-principles methods to compute Tc, and can treat theelectron-phonon interaction, electronic Coulomb interaction, and spin fluctuation (SF) fully non-empirically. This method has
been applied to mainly the phonon-mediated superconductors. For example, SCDFT is used to reveal the origin of the multiband superconductivity in MgB, the relationship between the structure and Tc of hydrogen sulfides. We plan to apply thismethod to a wide variety of materials and accelerate the first-principles exploration of superconductors. For this purpose, we aredeveloping an open-source software Superconducting-Toolkit (SCTK), and release that software on the Web. In this study, we
performed a benchmark to the simplest superconductors and non-superconductors, namely 35 elemental metals; we formulated
a method to treat SF together with the spin-orbit interaction (SOI) and investigate these two effects on Tc. We believe that thisbenchmark study will be a milestone for exploring superconductors with high-throughput computations and methodologicalimprovements in the future.
1.

Benchmark of density functional theory for superconductors in elemental materials: M. Kawamura, Y. Hizume andT. Ozaki, Phys. Rev. B 101, 134511 (2020).

2.

*Emergence of nearly flat bands through a kagome lattice embedded in an epitaxial two-dimensional Ge layer with

3.

First-principles study on the stability and electronic structure of monolayer GaSe with trigonal-antiprismatic structure:
H. Nitta, T. Yonezawa, A. Fleurence, Y. Yamada-Takamura and T. Ozaki, Phys. Rev. B 102, 235407 (2020).

4.

Unfolding optical transition weights of impurity materials for first-principles LCAO electronic structure calculations:
Y.-T. Lee, C.-C. Lee, M. Fukuda and T. Ozaki, Phys. Rev. B 102, 075143 (2020).

5.

*Formation of BN-covered silicene on ZrB /Si(111) by adsorption of NO and thermal processes: J. Yoshinobu,
26.

*Structural investigation of ternary PdRuM (M = Pt, Rh, or Ir) nanoparticles using first-principles calculations: S.-H.

7.

*Electronic structure of a (3×3)-ordered silicon layer on Al(111): Y. Sato, Y. Fukaya, M. Cameau, A. K. Kundu,

a bitriangular structure: A. Fleurence, C. -C. Lee, R. Friedlein, Y. Fukaya, S. Yoshimoto, K. Mukai, H. Yamane,
N. Kosugi, J. Yoshinobu, T. Ozaki and Y. Yamada-Takamura, Phys. Rev. B 102, 201102 (2020).

K. Mukai, H. Ueda, S. Yoshimoto, S. Shimizu, T. Koitaya, H. Noritake, C.-C. Lee, T. Ozaki, A. Fleurence, R. Friedlein
and Y. Yamada-Takamura, J. Chem. Phys. 153, 064702 (2020).
Hung, H. Akiba, O. Yamamuro and T. Ozaki, RSC Adv. 10, 16527 (2020).

D. Shiga, R. Yukawa, K. Horiba, C.-H. Chen, A. Huang, H.-T. Jeng, T. Ozaki, H. Kumigashira, M. Niibe and I.
* Joint research among groups within ISSP.

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Matsuda, Phys. Rev. Materials 4, 064005 (2020).
8.

Neural network atomic potential to investigate the dislocation dynamics in bcc iron: H. Mori and T. Ozaki, Phys. Rev.
Materials 4, 040601(R) (2020).

9.

*Vapochromism induced by intermolecular electron transfer coupled with hydrogen-bond formation in zinc dithiolene

complex: T. Fujino, M. Kawamura, T. Ozaki and H. Mori, J. Mater. Chem. C 8, 14939-14947 (2020).

10. First-principles adaptive-boost accelerated molecular dynamics simulation with effective boost potential construction
methods: a study of Li diffusion in Si crystal: M. Yamamoto, A. Ishii, S. Shinzato, S. Ogata and T. Ozaki, Japanese
Journal of Applied Physics 59, 125002 (2020).
11. Diverse densest binary sphere packings and phase diagram: R. Koshoji, M. Kawamura, M. Fukuda and T. Ozaki, Phys.
Rev. E 103, 023307 (2021).
12. †*Kω— Open-source library for the shifted Krylov subspace method of the form (zI - H)x = b: T. Hoshi, M. Kawamura,
K. Yoshimi, Y. Motoyama, T. Misawa, Y. Yamaji, S. Todo, N. Kawashima and T. Sogabe, Computer Physics Communications 258, 107536 (2021).
13. †*RESPACK: An ab initio tool for derivation of effective low-energy model of material: K. Nakamura, Y. Yoshimoto,
Y. Nomura, T. Tadano, M. Kawamura, T. Kosugi, K. Yoshimi, T. Misawa and Y. Motoyama, Computer Physics Communications 261, 107781 (2021).
14. Structure of one-dimensional monolayer Si nanoribbons on Ag(111): L. Feng, A. Shiotari, K. Yabuoshi, M. Fukuda,
T. Ozaki and Y. Sugimoto, Phys. Rev. Materials 5, 034002 (2021).
15. *The Simplest Model for Doped Poly(3,4-ethylenedioxythiophene) (PEDOT): Single-crystalline EDOT Dimer Radical
Cation Salts: R. Kameyama, T. Fujino, S. Dekura, M. Kawamura, T. Ozaki and H. Mori, Chem. Eur. J. 27, 6696 (2021).

Noguchi group
We have studied (1) Turing patterns on a vesicle by a reaction-diffusion system coupled with mechanochemical feedback, (2)the conformation of ultra-long-chain fatty acid in lipid bilayer, (3) the effects of cavitation on Karman vortex, and (4) soundwave propagation in a simple fluid. We also proposed (5) a new numerical method to calculate membrane mechanical properties.
1.

†Conformation of ultra-long-chain fatty acid in lipid bilayer: Molecular dynamics study: K. Kawaguchi, K. M.

2.

†Effects of cavitation on Kármán vortex behind circular-cylinder arrays: A molecular dynamics study: Y. Asano,3.

†Molecular dynamics simulation of soundwave propagation in a simple fluid: Y. Asano, H. Watanabe and H. Noguchi,

4.

†Virtual bending method to calculate bending rigidity, saddle-splay modulus, and spontaneous curvature of thin fluid

5.

Supramolecular Biocomposite Hydrogels Formed by Cellulose and Host–Guest Polymers Assisted by Calcium Ion
Complexes: H. Tsuchiya, G. Sinawang, T.-A. Asoh, M. Osaki, Y. Ikemoto, Y. Higuchi, H. Yamaguchi, A. Harada,
H. Uyama and Y. Takashima, Biomacromolecules 21, 3936 (2020).

6.

Pattern formation in reaction–diffusion system on membrane with mechanochemical feedback: N. Tamemoto and
H. Noguchi, Sci Rep 10, 19582 (2020).

7.

* 分子動力学計算による複雑流体中のカルマン渦の解析 : 浅野 優太 , 渡辺 宙志 , 野口 博司 , 分子シミュレーション学会誌

Nakagawa, S. Nakagawa, H. Shindou, H. Nagao and H. Noguchi, J. Chem. Phys. 153, 165101 (2020).

H. Watanabe and H. Noguchi, J. Chem. Phys. 152, 034501 (2020).
J. Chem. Phys. 153, 124504 (2020).

membranes: H. Noguchi, Phys. Rev. E 102, 053315 (2020).

" アンサンブル " 22, 157-162 (2020).

8.

†Rational Design Principles of Attenuated Cationic Lytic Peptides for Intracellular Delivery of Biomacromolecules:

9.

高分子材料の破壊に関する粗視化シミュレーション : 樋口 祐次 , 分子シミュレーション学会誌「アンサンブル」22, 216-221

N. Tamemoto, M. Akishiba, K. Sakamoto, K. Kawano, H. Noguchi and S. Futaki, Mol. Pharmaceutics 17, 2175-2185(2020).
(2020).

10. Coarse-grained molecular dynamics simulations of void generation and growth processes in the fracture of the lamellar
structure of polyethylene: Y. Higuchi, Phys. Rev. E 103, 042502 (2021).
† Joint research with outside partners.

ISSP Activity Report 2020179

11. Undulation of a moving fluid membrane pushed by filament growth: H. Noguchi and O. Pierre-Louis, Sci Rep 11, 7985
(2021).

Yoshimi group
We have developed and enhanced the usability of programs adopted in the project for advancement of software usability inmaterials science (PASUMS). Our group's activity of 2020 include development of (1) optimization tools for PHYSics basedon Bayesian Optimization (PHYSBO), (2) 2DMAT, and the enhancement of usability for (3) MateriApps Installer. In addition,
we have studied (1) derivation and analysis of low-energy effective Hamiltonian of organic conductors using software packages(RESPACK and HΦ) developed in PASUMS and (2) application of sparse modeling in quantum many body problems.
1.

†Finite Temperature Properties of Geometrically Charge Frustrated Systems: K. Yoshimi, M. Naka and H. Seo, J. Phys.

2.

†Sparse Modeling in Quantum Many-Body Problems: J. Otsuki, M. Ohzeki, H. Shinaoka and K. Yoshimi, J. Phys. Soc.

3.

†Transport properties of the organic Dirac electron system α-(BEDT−TSeF) I : D. Ohki, K. Yoshimi and A. Kobayashi,
2 3Phys. Rev. B 102, 235116 (2020).

4.

†Electronic correlation and geometrical frustration in molecular solids: A systematic ab initio study of β'−X[Pd(dmit) ] :2 2

5.

†Sparse sampling and tensor network representation of two-particle Green's functions: H. Shinaoka, D. Geffroy,

6.

†Multiple-magnon excitations shape the spin spectrum of cuprate parent compounds: D. Betto, R. Fumagalli, L. Marti-

7.

†*DSQSS: Discrete Space Quantum Systems Solver: Y. Motoyama, K. Yoshimi, A. Masaki-Kato, T. Kato and

8.

†*Kω— Open-source library for the shifted Krylov subspace method of the form (zI - H)x = b: T. Hoshi, M. Kawamura,

9.

†*RESPACK: An ab initio tool for derivation of effective low-energy model of material: K. Nakamura, Y. Yoshimoto,Soc. Jpn. 89, 034003 (2020).
Jpn. 89, 012001 (2020).

T. Misawa, K. Yoshimi and T. Tsumuraya, Phys. Rev. Research 2, 032072 (2020).

M. Wallerberger, J. Otsuki, K. Yoshimi, E. Gull and J. Kuneš, SciPost Phys. 8, 012 (2020).

nelli, M. Rossi, R. Piombo, K. Yoshimi, D. D. Castro, E. D. Gennaro, A. Sambri, D. Bonn, G. A. Sawatzky, L. Braicovich, N. B. Brookes, J. Lorenzana and G. Ghiringhelli, Phys. Rev. B 103, L140409 (2021).

N. Kawashima, Computer Physics Communications 264, 107944 (2021).

K. Yoshimi, Y. Motoyama, T. Misawa, Y. Yamaji, S. Todo, N. Kawashima and T. Sogabe, Computer Physics Communications 258, 107536 (2021).

Y. Nomura, T. Tadano, M. Kawamura, T. Kosugi, K. Yoshimi, T. Misawa and Y. Motoyama, Computer Physics Communications 261, 107781 (2021).

Materials Synthesis and Characterization group1.

Anisotropic Magnetic Field Dependence of Specific Heat in the Cubic Symmetric Quadrupolar Kondo Compound
Pr0.05La0.95Pb3: T. Kawae, M. Koga, Y. Sato, Y. Inagaki, T. Fujiwara, H. S. Suzuki and T. Kitai, J. Phys. Soc. Jpn. 89,
063704 (2020).

2.

Kondo-Induced Giant Isotropic Negative Thermal Expansion: D. G. Mazzone, M. Dzero, AM. M. Abeykoon,
H. Yamaoka, H. Ishii, N. Hiraoka, J. -P. Rueff, J. M. Ablett, K. Imura, H. S. Suzuki, J. N. Hancock and I. Jarrige, Phys.
Rev. Lett. 124, 125701 (2020).

3.

*Anisotropic Triangular Lattice Realized in Rhenium Oxychlorides A ReO Cl (A = Ba, Sr): D. Hirai, T. Yajima,
3
5 2

4.

*Spin–orbit-coupled metal candidate PbRe O : S. Tajima, D. Hirai, T. Yajima, D. Nishio-Hamane, Y. Matsubayashi and
2 6

K. Nawa, M. Kawamura and Z. Hiroi, Inorg. Chem. 59, 10025 (2020).
Z. Hiroi, Journal of Solid State Chemistry 288, 121359 (2020).

5.

Magnetic properties of oxides with high concentrations of rare-earth elements R6AO12 (R = rare-earth element, A = Moor W): M. Hase, N. Tsujii, H. S. Suzuki, O. Sakai and H. Mamiya, Journal of Magnetism and Magnetic Materials 523,
167539 (2020).

6.

*Devil's staircase transition of the electronic structures in CeSb: K. Kuroda, Y. Arai, N. Rezaei, S. Kunisada,

S. Sakuragi, M. Alaei, Y. Kinoshita, C. Bareille, R. Noguchi, M. Nakayama, S. Akebi, M. Sakano, K. Kawaguchi,
M. Arita, S. Ideta, K. Tanaka, H. Kitazawa, K. Okazaki, M. Tokunaga, Y. Haga, S. Shin, H. S. Suzuki, R. Arita andT. Kondo, Nat Commun 11, 2888/1-9 (2020).
* Joint research among groups within ISSP.

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ISSP Activity Report 2020

Neutron Science Laboratory
Yamamuro group
Our laboratory is studying chemical physics of complex condensed matters by using neutron scattering, X-ray diffraction,
calorimetric, dielectric, and viscoelastic techniques. Our target materials are glasses, liquids, and various disordered systems.
The highlight of this year is the inelastic neutron scattering (INS) experiment of vapor-deposited CS2 glass which was
performed on AMATERAS in J-PARC MLF. By combining the results of CS2 and CCl4, which was measured in 2018, we
have found the general relation between the low-energy excitations and local structures in the glass. The boson peak appears
independently of the local structure of the glass, while the dispersive phonon excitations adjacent to the boson peak strongly
depends on the quasi-network structure of the glass. Following the quasi-elastic neutron scattering (QENS) of a novel hydrogencluster material Li6NbH11 measured last year, the QENS experiment of Li5MoH11 was carried out on DNA in J-PARC MLF.
Both data demonstrate that the MH9 cluster is rotating rapidly with widely-distributed relaxation times, which may be causedby the conducting (positionally disordered) Li ions. The correlation between the conducting Li ions and hydrogen clusters wasfound also in the calorimetric experiment of novel Li conductors containing cage-like ions, Li(CB9H10) and 0.7Li(CB9H10)0.3Li(CB11H12). The synchrotron-radiation X-ray diffraction experiment was conducted in SPring-8 for the glass of a novel
metal-organic framework (MOF) material containing CO2 as guest molecules.
1.

Dynamics of Atomic Hydrogen in Palladium Probed by Neutron Spectroscopy: M. Kofu and O. Yamamuro, J. Phys.
Soc. Jpn. 89, 051002 (2020).

2.

Rational Synthesis for a Noble Metal Carbide: T. Wakisaka, K. Kusada, D. Wu, T. Yamamoto, T. Toriyama, S. Matsumura, H. Akiba, O. Yamamuro, K. Ikeda, T. Otomo, N. Palina, Y. Chen, L. S. R. Kumara, C. Song, O. Sakata, W. Xie,
M. Koyama, Y. Kubota, S. Kawaguchi, R. L. Arevalo, S. M. Aspera, E. F. Arguelles, H. Nakanishi and H. Kitagawa,J. Am. Chem. Soc. 142, 1247 (2020).

3.

New Insights on the Formation Process and Thermodynamics of the α-Phase PdH(D)x through Direct Enthalpy
Measurement of H(D) Dissolution: S. Dekura, H. Akiba, O. Yamamuro, H. Kobayashi, M. Maesato and H. Kitagawa,J. Phys. Chem. C 124, 8663-8668 (2020).

4.

Nanometric Fluctuations of Sound Velocity in Alkali Borate Glasses and Fragility of Respective Melts: S. Kojima, V. N.
Novikov, M. Kofu and O. Yamamuro, Phys. Status Solidi B 257, 2000073 (2020).

5.

Nanoscale Relaxation in “Water-in-Salt” and “Water-in-Bisalt” Electrolytes: M. A. González, O. Borodin, M. Kofu,
K. Shibata, T. Yamada, O. Yamamuro, K. Xu, D. L. Price and M. -L. Saboungi, J. Phys. Chem. Lett. 11, 7279 (2020).

6.

*Structural investigation of ternary PdRuM (M = Pt, Rh, or Ir) nanoparticles using first-principles calculations: S.-H.
Hung, H. Akiba, O. Yamamuro and T. Ozaki, RSC Adv. 10, 16527 (2020).

7.

Quasielastic Neutron Scattering Study on Polymorphism of Glycerol Deuterated Triacylglycerols: Comparison
with Saturated, Trans-unsaturated and Cis-unsaturated Triacylglycerols: C. Takechi, T. Kawaguchi, F. Kaneko andO. Yamamuro, Chem. Lett. 50, 435 (2021).

8.

ガラス転移温度 : 山室 修 ,「化学便覧基礎編改訂第 6 版」, 10.15, 日本化学会編 , ( 丸善出版 , 2020), 77-81.

Masuda group
The goal of our research is to discover a new quantum phenomenon and to reveal the mechanism of it. In this fiscal year westudied the following topics; Helical and collinear spin density wave order in the S = 1/2 one-dimensional frustrated chain
compound NaCuMoO4(OH) investigated by neutron scattering, Magnetic order in the chemically substituted frustrated antiferromagnet CsCrF4, Zero-energy excitation in the classical kagome antiferromagnet NaBa2Mn3F11, Magnetic correlations in
YBaCo4O7 on kagome and triangular lattices, etc.
1.

Analysis of Field-Induced Nonreciprocal Magnon in Noncollinear Magnet and Application to S = 1 Triangular Antiferromagnet CsFeCl3: M. Matsumoto, S. Hayashida and T. Masuda, J. Phys. Soc. Jpn. 89, 034710(1-17) (2020).

2.

Horizontal Line Nodes in Sr2RuO4 Proved by Spin Resonance: K. Iida, M. Kofu, K. Suzuki, N. Murai, S. OhiraKawamura, R. Kajimoto, Y. Inamura, M. Ishikado, S. Hasegawa, T. Masuda, Y. Yoshida, K. Kakurai, K. Machida andS. Lee, J. Phys. Soc. Jpn. 89, 053702(1-5) (2020).

3.

Mossbauer Study of Rare-earth Ferroborate NdFe3(BO3)4: S. Nakamura, T. Masuda, K. Ohgushi and T. Katsufuji,
J. Phys. Soc. Jpn. 89, 084703(1-6) (2020).

4.

†*Emergent spin-1 Haldane gap and ferroelectricity in a frustrated spin- 1/2 ladder: H. Ueda, S. Onoda, Y. Yamaguchi,

T. Kimura, D. Yoshizawa, T. Morioka, M. Hagiwara, M. Hagihala, M. Soda, T. Masuda, T. Sakakibara, K. Tomiyasu,† Joint research with outside partners.

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S. Ohira-Kawamura, K. Nakajima, R. Kajimoto, M. Nakamura, Y. Inamura, N. Reynolds, M. Frontzek, J. S. White,
M. Hase and Y. Yasui, Phys. Rev. B 101, 140408(1-6) (2020).
5.

*Helical and collinear spin density wave order in the S = 1/2 one-dimensional frustrated chain compound
NaCuMoO4(OH) investigated by neutron scattering: S. Asai, T. Oyama, K. Nawa, A. Nakao, K. Munakata,
K. Kuwahara, M. Hagihala, S. Itoh, Z. Hiroi and T. Masuda, Phys. Rev. B 101, 144437(1-8) (2020).

6.

Magnetic correlations in YBaCo4O7 on kagome and triangular lattices: M. Soda, S. Itoh, T. Yokoo, G. Ehlers,
H. Kawano-Furukawa and T. Masuda, Phys. Rev. B 101, 214444(1-7) (2020).

7.

Magnetic order in the chemically substituted frustrated antiferromagnet CsCrF4: S. Hayashida, M. Hagihala,
M. Avdeev, Y. Miura, H. Manaka and T. Masuda, Phys. Rev. B 102, 174440(1-6) (2020).

8.

Spin waves in the two-dimensional honeycomb lattice XXZ-type van der Waals antiferromagnet CoPS3: C. Kim,
J. Jeong, P. Park, T. Masuda, S. Asai, S. Itoh, H.-S. Kim, A. Wildes and J.-G. Park, Phys. Rev. B 102, 184429(1-8)(2020).

9.

*Zero-energy

excitation in the classical kagome antiferromagnet NaBa2Mn3F11: S. Hayashida, H. Ishikawa,Y. Okamoto, T. Okubo, Z. Hiroi, G. J. Nilsen, H. Mutka and T. Masuda, Phys. Rev. B 101, 214409 (2020).

10. The f-electron State of the Heavy Fermion Superconductor NpPd5Al2 and the Isostructural Family: N. Metoki, A. A.
Aczel, D. Aoki, S. Chi, J. A. Fernandez-Baca, J.-C. Griveau, M. Hagihala, T. Hong, Y. Haga, K. Ikeuchi, Y. Inamura,
K. Kamazawa, R. Kajimoto, H. Kitazawa, T. Masuda, M. Matsuda, M. Nakamura, J. Ohtsuki, D. Pajerowski, H. S.
Suzuki, E. Yamamoto and H. Yamauchi, JPS Conf. Proc. 30, 011123(1-6) (2020).
11. Establishing the carrier scattering phase diagram for ZrNiSn-based half-Heusler thermoelectric materials: Q. Ren, C. Fu,
Q. Qiu, S. Dai, Z. Liu, T. Masuda, S. Asai, M. Hagihala, S. Lee, S. Torri, T. Kamiyama, L. He, X. Tong, C. Felser, D. J.
Singh, T. Zhu, J. Yang and J. Ma, Nat Commun 11, 3142(1-9) (2020).
12. †*Gapless spin liquid in a square-kagome lattice antiferromagnet: M. Fujihala, K. Morita, R. Mole, S. Mitsuda,
T. Tohyama, S.-I. Yano, D. Yu, S. Sota, T. Kuwai, A. Koda, H. Okabe, H. Lee, S. Itoh, T. Hawai, T. Masuda,
H. Sagayama, A. Matsuo, K. Kindo, S. Ohira-Kawamura and K. Nakajima, Nat Commun 11, 3429 (2020).
13. Fermionic order by disorder in a van der Waals antiferromagnet: R. Okuma, D. Ueta, S. Kuniyoshi, Y. Fujisawa,B. Smith, C. H. Hsu, Y. Inagaki, W. Si, T. Kawae, H. Lin, F. C. Chuang, T. Masuda, R. Kobayashi and Y. Okada, Sci
Rep 10, 15311(8pages) (2020).
14. Dynamical Studies in Condensed Matter on High Resolution Chopper Spectrometer (HRC) —2nd Phase of HRC
Project—: S. Itoh, T. Masuda, T. Yokoo, H. Yoshizawa, M. Soda, S. Asai, Y. Ikeda, S. Ibuka, M. Yoshida, T. Hawai,
H. Saito, D. Kawana, R. Sugiura, T. Asami and Y. Ihata, JPS Conf. Proc. 33, 011058(1-7) (2021).

Nakajima group
Nakajima group has been studying magnetic materials showing cross-correlated phenomena related to topologically-nontrivial
magnetic structures. One example is magnetic skyrmion, which is vortex-like spin order behaving like a particle. In thisyear, we investigated crystallization process of magnetic skyrmions in a chiral magnet MnSi by means of neutron resonancespin-echo spectroscopy in J-PARC. We have been collaborating with scientists in KEK and Kyoto university to develop theresonance-type neutron spin echo spectrometer, and successfully observed spin echo signals revealing that the spin fluctuations
near the phase boundary between the paramagnetic and skyrmion lattice phases has a characteristic relaxation time of 1 ns. We
also studied rare-earth based skyrmion materials by resonant X-ray magnetic scattering, and also applied polarized small-angle
neutron scattering technique to a polar crystal hosting Neel-type magnetic skyrmion lattice.
1.

中性子散乱を用いた磁気スキルミオン研究 : 中島 多朗 , 有馬 孝尚 , 固体物理 55, 265-274 (2020).

2.

Crystallization of magnetic skyrmions in MnSi investigated by neutron spin echo spectroscopy: T. Nakajima, T. Oda,
M. Hino, H. Endo, K. Ohishi, K. Kakurai, A. Kikkawa, Y. Taguchi, Y. Tokura and T.-H. Arima, Phys. Rev. Research 2,043393 (2020).

3.

Nanometric square skyrmion lattice in a centrosymmetric tetragonal magnet: N. D. Khanh, T. Nakajima, X. Yu, S. Gao,
K. Shibata, M. Hirschberger, Y. Yamasaki, H. Sagayama, H. Nakao, L. Peng, K. Nakajima, R. Takagi, T.-H. Arima,
Y. Tokura and S. Seki, Nat. Nanotechnol. 15, 444 (2020).

4.

Direct Observation of Cycloidal Spin Modulation and Field-induced Transition in Néel-type Skyrmion-hosting
VOSe2O5: T. Kurumaji, T. Nakajima, A. Feoktystov, E. Babcock, Z. Salhi, V. Ukleev, T.-H. Arima, K. Kakurai and
Y. Tokura, J. Phys. Soc. Jpn. 90, 024705 (2021).

* Joint research among groups within ISSP.

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Mayumi group
We have discovered that slide-ring gels, in which polymer chains are cross-linked by ring molecules, show strain-induced
crystallization (SIC) under uniaxial stretching. The occurrence of SIC improves significantly the mechanical toughness of slidering gels. In addition, the crystalline formation is reversible in response to elongation and retraction, which results in the highmechanical reversibility under cyclic deformations. The novel toughening mechanism of hydrogels by SIC enables the simultaneous improvement of toughness and reversibility required for the applications of hydrogels as biomaterials, such as artificial
cartilage and prosthetic joints.

International MegaGauss Science Laboratory
Kindo group
We have examined an Fulde–Ferrell–Larkin–Ovchinnikov phase using some angle-resolved physical property measurements inpulsed magnetic fields, which have unveiled details of pair-breaking effects of the magnetic field on this phase. Magnetism of
the 4d and 5d transition metal double perovskites with strong spin-orbit coupling are investigated up to around 65 T. We discovered the ligand dependent magnetism in Cs2MX6 (M= Nb, Ta, X = Cl, Br) and the magnetic field induced phase transition at 50
T in Ba2CaReO6.
1.

†Ga Substitution Effect on the Valence Transition of Eu Pt Al : K. Oyama, A. Mitsuda, H. Wada, Y. Narumi,
2 6 15

2.

*Kitaev Spin Liquid Candidate Os Cl Comprised of Honeycomb Nano-Domains: K. Kataoka, D. Hirai, T. Yajima,x 3

3.

†Multi-Step

Magnetic Transitions in EuNiIn 4: S. Ikeda, K. Kaneko, Y. Tanaka, T. Kawasaki, T. Hanashima,
K. Munakata, A. Nakao, R. Kiyanagi, T. Ohhara, K. Mochizuki, A. Kondo, K. Kindo, Y. Homma, M. D. Frontzek and
H. Kobayashi, J. Phys. Soc. Jpn. 89, 014707(1-7) (2020).

4.

†Vanishment of Metamagnetic Transition in the Metal-to-Insulator Transition Compound BaVS under High Pressure:3

5.

†Angle-dependent

6.

†Data-driven determination of the spin Hamiltonian parameters and their uncertainties: The case of the zigzag-chain

7.

*Enhanced spin correlations in the Bose-Einstein condensate compound Sr Cr O : T. Nomura, Y. Skourski, D. L.
3 2 8

8.

*Observation of in-plane magnetic field induced phase transitions in FeSe: J. M. Ok, C. I. Kwon, Y. Kohama, J. S. You,

9.

*Quantum oscillations and magnetic field induced Fermi surface reconstruction in the charge density wave state of

M. Hagiwara, R. Takahashi, H. Wadati, H. Setoyama and K. Kindo, J. Phys. Soc. Jpn. 89, 114713 (2020).

D. Nishio-Hamane, R. Ishii, K.-Y. Choi, D. Wulferding, P. Lemmens, S. Kittaka, T. Sakakibara, H. Ishikawa, A. Matsuo,
K. Kindo and Z. Hiroi, J. Phys. Soc. Jpn. 89, 114709(1-9) (2020).

T. Tahara, T. Kida, Y. Narumi, T. Takeuchi, H. Nakamura, K. Miyake, K. Kindo and M. Hagiwara, J. Phys. Soc. Jpn. 89,
064711(1-5) (2020).

nontrivial phase in the Weyl semimetal NbAs with anisotropic Fermi surface: M. Komada,H. Murakawa, M. S. Bahramy, T. Kida, K. Yokoi, Y. Narumi, K. Kindo, M. Hagiwara, H. Sakai and N. Hanasaki, Phys.
Rev. B 101, 045135(1-6) (2020).
compound KCu4P3O12: R. Tamura, K. Hukushima, A. Matsuo, K. Kindo and M. Hase, Phys. Rev. B 101, 224435(1-9)(2020).

Quintero-Castro, A. A. Zvyagin, A. V. Suslov, D. Gorbunov, S. Yasin, J. Wosnitza, K. Kindo, A. T. M. N. Islam, B. Lake,
Y. Kohama, S. Zherlitsyn and M. Jaime, Phys. Rev. B 102, 165144 (2020).
S. K. Park, J.-H. Kim, Y. J. Jo, E. S. Choi, K. Kindo, W. Kang, K.-S. Kim, E. G. Moon, A. Gurevich and J. S. Kim,
Phys. Rev. B 101, 224509 (2020).
A0.9Mo6O17 (A = Na, K): H. P. Zhu, M. Yang, J. Z. Ke, H. K. Zuo, T. Peng, J. F. Wang, Y. Liu, X. Xu, Y. Kohama,
K. Kindo and M. Greenblatt, Phys. Rev. B 102, 235164 (2020).

10. Thermal and magnetoelastic properties of α−RuCl3 in the field-induced low-temperature states: R. Schönemann,
S. Imajo, F. Weickert, J. Yan, D. G. Mandrus, Y. Takano, E. L. Brosha, P. F. S. Rosa, S. E. Nagler, K. Kindo and M.
Jaime, Phys. Rev. B 102, 214432(1-7) (2020).
11. *Anisotropic Fully Gapped Superconductivity Possibly Mediated by Charge Fluctuations in a Nondimeric Organic
Complex: S. Imajo, H. Akutsu, R. Kurihara, T. Yajima, Y. Kohama, M. Tokunaga, K. Kindo and Y. Nakazawa, Phys.
Rev. Lett. 125, 177002 (2020).
12. †Nonmagnetic Ground States and a Possible Quadrupolar Phase in 4d and 5d Lacunar Spinel Selenides GaM4Se8 (M =† Joint research with outside partners.

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183

Nb, Ta): H. Ishikawa, T. Yajima, A. Matsuo, Y. Ihara and K. Kindo, Phys. Rev. Lett. 124, 227202(1-6) (2020).
13. †*Particle-Hole Symmetry Breaking in a Spin-Dimer System TlCuCl3 Observed at 100 T: X. -G. Zhou, Y. Yao, Y. H.
Matsuda, A. Ikeda, A. Matsuo, K. Kindo and H. Tanaka, Phys. Rev. Lett. 125, 267207 1-6 (2020).
14. †*Synthesis, Structure, and Anomalous Magnetic Ordering of the Spin-1/2 Coupled Square Tetramer System K(NbO)
Cu4(PO4)4: K. Kimura, D. Urushihara, T. Asaka, M. Toyoda, A. Miyake, M. Tokunaga, A. Matsuo, K. Kindo, K.
Yamauchi and T. Kimura, Inorg. Chem. 59, 10986-10995 (2020).
15. *Extracting the Chiral Contribution to the Negative Longitudinal Magnetoresistance in Epitaxial Pr2Ir2O7 Thin Films:
T. Ohtsuki, Z. Tian, A. Endo, M. Halim, S. Katsumoto, Y. Kohama, K. Kindo, M. Lippmaa and S. Nakatsuji, JPS Conf.
Proc. 30, 011181 (1-6) (2020).
16. Avoided quantum criticality and cluster-glass formation in itinerant ferromagnet Sr1−x(La0.5K0.5)xRuO3: R. Iwahara,
R. Sugawara, *. Rahmanto, Y. Honma, K. Matsuoka, A. Matsuo, K. Kindo, K. Tenya and M. Yokoyama, Phys. Rev.
Materials 4, 074404(1-8) (2020).
17. *Improved accuracy in high-frequency AC transport measurements in pulsed high magnetic fields: H. Mitamura,
R. Watanuki, E. Kampert, T. Förster, A. Matsuo, T. Onimaru, N. Onozaki, Y. Amou, K. Wakiya, K. T. Matsumoto,I. Yamamoto, K. Suzuki, S. Zherlitsyn, J. Wosnitza, M. Tokunaga, K. Kindo and T. Sakakibara, Review of Scientific
Instruments 91, 125107/1-25 (2020).
18. †*Gapless spin liquid in a square-kagome lattice antiferromagnet: M. Fujihala, K. Morita, R. Mole, S. Mitsuda,
T. Tohyama, S.-I. Yano, D. Yu, S. Sota, T. Kuwai, A. Koda, H. Okabe, H. Lee, S. Itoh, T. Hawai, T. Masuda,
H. Sagayama, A. Matsuo, K. Kindo, S. Ohira-Kawamura and K. Nakajima, Nat Commun 11, 3429 (2020).
19. *High-field phase diagram of Ni3V2O8 studied by specific heat and magnetocaloric effect measurements: C. Dong,
Y. Kohama, Z. Z. He, X. T. Han, K. Sato, A. Matsuo, K. Kindo, M. Yang and J. F. Wang, J. Phys.: Condens. Matter 33,
205402 (2021).
20. Ligand dependent magnetism of the J = 3/2 Mott insulator Cs2MX6 (M = Ta, Nb, X = Br, Cl): H. Ishikawa, T. Yajima,
A. Matsuo and K. Kindo, J. Phys.: Condens. Matter 33, 125802(1-6) (2021).
21. Magnetization Process in EuCo2P2 and EuT2Ge2 (T: transition metal): Comparison of Experiment and Theory:
T. Takeuchi, T. Tahara, T. Kida, Y. Narumi, M. Hagiwara, K. Kindo, W. Iha, Y. Ashitomi, T. Yara, M. Nakashima,
Y. Amako, M. Hedo, T. Nakama and Y. Onuki, J. Phys. Soc. Jpn. 90, 034709(1-15) (2021).
22. †*Spin Excitations of the S = 1/2 One-Dimensional Ising-Like Antiferromagnet BaCo2V2O8 in Transverse Magnetic
Fields: A. Okutani, H. Onishi, S. Kimura, T. Takeuchi, T. Kida, M. Mori, A. Miyake, M. Tokunaga, K. Kindo and
M. Hagiwara, J. Phys. Soc. Jpn. 90, 044704/1-9 (2021).
23. †*Geometrical Hall effect and momentum-space Berry curvature from spin-reversed band pairs: M. Hirschberger,
Y. Nomura, H. Mitamura, A. Miyake, T. Koretsune, Y. Kaneko, L. Spitz, Y. Taguchi, A. Matsuo, K. Kindo, R. Arita,
M. Tokunaga and Y. Tokura, Phys. Rev. B 103, L041111(1-6) (2021).
24. Symmetry change of d-wave superconductivity in κ-type organic superconductors: S. Imajo, K. Kindo and
Y. Nakazawa, Phys. Rev. B 103, L060508(1-5) (2021).
25. *Compact megajoule-class pulsed power supply for generating long-pulsed magnetic fields: K. Matsui, T. Kanda,
Y. Ihara, K. Kindo and Y. Kohama, Review of Scientific Instruments 92, 024711 (2021).
26. *High-resolution calorimetry in pulsed magnetic fields: S. Imajo, C. Dong, A. Matsuo, K. Kindo and Y. Kohama,
Review of Scientific Instruments 92, 043901 (2021).

Tokunaga group
In this year, we have developed or improved several measurements in high magnetic fields. Using fast capacitance measurements, we have achieved high-precision measurements of magnetostriction, dielectric constants, and magnetocaloric effects inpulsed-high magnetic fields. We utilize polarizing microscopy to visualize domain structures in CeSb and Cd2Re2O7 and study
the dynamics of superconducting vortices and field-induced structural transitions in metamagnetic shape memory alloys using
a high-speed camera. Utilizing various measurement techniques, we studied magnetic field-induced phase transitions in several
heavy fermion and multiferroic materials and magnetotransport properties of topological semimetals. In elemental tellurium, asemiconductor with a chiral crystal structure, our high-field magnetotransport study revealed the existence of metallic states on
the as-cleavage surfaces of single crystals.
1.

*105Pd NMR and NQR study of the cubic heavy fermion system Ce Pd Si : I. Jakovac, M. Horvatic, E. F. Schwier,
3 20 6* Joint research among groups within ISSP.

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A. Prokofiev, S. Paschen, H. Mitamura, T. Sakakibara and M. S. Grbic, J. Phys.: Condens. Matter 32, 245601(1-7)(2020).
2.

*Domain Control by Adjusting Anisotropic Stress in Pyrochlore Oxide Cd Re O : S. Tajima, D. Hirai, Y. Kinoshita,
2 2 7

3.

†*Bulk quantum Hall effect of spin-valley coupled Dirac fermions in the polar antiferromagnet BaMnSb : H. Sakai,
24.

High-field ultrasonic study of quadrupole ordering and crystal symmetry breaking in CeRhIn5: R. Kurihara, A. Miyake,
M. Tokunaga, Y. Hirose and R. Settai, Phys. Rev. B 101, 155125/1-8 (2020).

5.

†Intriguing behavior of UCo Rh Ge ferromagnets in magnetic field along the axis: J. Pospíšil, Y. Haga, A. Miyake,
1-xx
S. Kambe, Y. Tokunaga, M. Tokunaga, E. Yamamoto, P. Proschek, J. Volný and V. Sechovský, Phys. Rev. B 102,024442/1-13 (2020).

6.

Magnetic phase diagram enriched by chemical substitution in a noncentrosymmetric helimagnet: T. Sato, Y. Araki,
A. Miyake, A. Nakao, N. Abe, M. Tokunaga, S. Kimura, Y. Tokunaga and T.-H. Arima, Phys. Rev. B 101, 054414/1-6(2020).

7.

†Magnetic structures and quadratic magnetoelectric effect in LiNiPO beyond 30 T: E. Fogh, T. Kihara, R. Toft4

8.

*Magnetotransport properties of tellurium under extreme conditions: K. Akiba, K. Kobayashi, T. C. Kobayashi,

9.

†Metamagnetic transitions and magnetoelectric responses in the chiral polar helimagnet Ni InSbO : Y. Araki, T. Sato, Y.
2
6

M. Tokunaga, K. Akiba, T. C. Kobayashi, H. T. Hirose and Z. Hiroi, J. Phys. Soc. Jpn. 89, 114711 (2020).

H. Fujimura, S. Sakuragi, M. Ochi, R. Kurihara, A. Miyake, M. Tokunaga, T. Kojima, D. Hashizume, T. Muro, K.
Kuroda, T. Kondo, T. Kida, M. Hagiwara, K. Kuroki, M. Kondo, K. Tsuruda, H. Murakawa and N. Hanasaki, Phys. Rev.
B 101, 081104/1-7 (2020).

Petersen, M. Bartkowiak, Y. Narumi, O. Prokhnenko, A. Miyake, M. Tokunaga, K. Oikawa, M. K. Sørensen, J. C.
Dyrnum, H. Grimmer, H. Nojiri and N. B. Christensen, Phys. Rev. B 101, 024403/1-12 (2020).
R. Koezuka, A. Miyake, J. Gouchi, Y. Uwatoko and M. Tokunaga, Phys. Rev. B 101, 245111(1-6) (2020).

Fujima, N. Abe, M. Tokunaga, S. Kimura, D. Morikawa, V. Ukleev, Y. Yamasaki, C. Tabata, H. Nakao, Y. Murakami, H.
Sagayama, K. Ohishi, Y. Tokunaga and T. Arima, Phys. Rev. B 102, 054409/1-8 (2020).

10. †Strong magnetic anisotropy and unusual magnetic field reinforced phase in URhSn with a quasi-kagome structure:
Y. Shimizu, A. Miyake, A. Maurya, F. Honda, A. Nakamura, Y. J. Sato, D. Li, Y. Homma, M. Yokoyama, Y. Tokunaga,
M. Tokunaga and D. Aoki, Phys. Rev. B 102, 134411/1-11 (2020).
11. *Anisotropic Fully Gapped Superconductivity Possibly Mediated by Charge Fluctuations in a Nondimeric Organic
Complex: S. Imajo, H. Akutsu, R. Kurihara, T. Yajima, Y. Kohama, M. Tokunaga, K. Kindo and Y. Nakazawa, Phys.
Rev. Lett. 125, 177002 (2020).
12. †Dynamic evolution of flux distributions in a pulse-driven superconductor by high-speed magneto-optical imaging:
H. Kurokawa, Y. Kinoshita, F. Nabeshima, M. Tokunaga and A. Maeda, Appl. Phys. Lett. 116, 262601/1-5 (2020).
13. †*Synthesis, Structure, and Anomalous Magnetic Ordering of the Spin-1/2 Coupled Square Tetramer System K(NbO)
Cu4(PO4)4: K. Kimura, D. Urushihara, T. Asaka, M. Toyoda, A. Miyake, M. Tokunaga, A. Matsuo, K. Kindo,
K. Yamauchi and T. Kimura, Inorg. Chem. 59, 10986-10995 (2020).
14. Anisotropic Quantum Transport through a Single Spin Channel in the Magnetic Semiconductor EuTiO3: K. Maruhashi,
K. S. Takahashi, M. S. Bahramy, S. Shimizu, R. Kurihara, A. Miyake, M. Tokunaga, Y. Tokura and M. Kawasaki, Adv.
Mater. 32, 1908315/1-10 (2020).
15. †High-Mobility 2D Hole Gas at a SrTiO3 Interface: L. D. Anh, S. Kaneta, M. Tokunaga, M. Seki, H. Tabata, M. Tanaka
and S. Ohya, Adv. Mater. 32, 1906003/1-7 (2020).
16. Magnetic field induced antiferromagnetic cone structure in multiferroic BiFeO3: M. Matsuda, S. E. Dissanayake,
T. Hong, Y. Ozaki, T. Ito, M. Tokunaga, X. Z. Liu, M. Bartkowiak and O. Prokhnenko, Phys. Rev. Materials 4,034412/1-6 (2020).
17. Capacitive detection of magnetostriction, dielectric constant, and magneto-caloric effects in pulsed magnetic fields:
A. Miyake, H. Mitamura, S. Kawachi, K. Kimura, T. Kimura, T. Kihara, M. Tachibana and M. Tokunaga, Review of
Scientific Instruments 91, 105103/1-9 (2020).
18. *Improved accuracy in high-frequency AC transport measurements in pulsed high magnetic fields: H. Mitamura,
R. Watanuki, E. Kampert, T. Förster, A. Matsuo, T. Onimaru, N. Onozaki, Y. Amou, K. Wakiya, K. T. Matsumoto,I. Yamamoto, K. Suzuki, S. Zherlitsyn, J. Wosnitza, M. Tokunaga, K. Kindo and T. Sakakibara, Review of Scientific
Instruments 91, 125107/1-25 (2020).
† Joint research with outside partners.

ISSP Activity Report 2020185

19. *Devil's staircase transition of the electronic structures in CeSb: K. Kuroda, Y. Arai, N. Rezaei, S. Kunisada,
S. Sakuragi, M. Alaei, Y. Kinoshita, C. Bareille, R. Noguchi, M. Nakayama, S. Akebi, M. Sakano, K. Kawaguchi,
M. Arita, S. Ideta, K. Tanaka, H. Kitazawa, K. Okazaki, M. Tokunaga, Y. Haga, S. Shin, H. S. Suzuki, R. Arita andT. Kondo, Nat Commun 11, 2888/1-9 (2020).
20. †High-field magnetization and magnetic phase diagram of metamagnetic shape memory alloys Ni50−Co Mn31.5Ga18.5(x = 9 and 9.7): T. Kihara, X. Xu, A. Miyake, Y. Kinoshita, M. Tokunaga, Y. Adachi and T. Kanomata, Scripta Materialia
181, 25-29 (2020).
21. †*Spin Excitations of the S = 1/2 One-Dimensional Ising-Like Antiferromagnet BaCo2V2O8 in Transverse Magnetic
Fields: A. Okutani, H. Onishi, S. Kimura, T. Takeuchi, T. Kida, M. Mori, A. Miyake, M. Tokunaga, K. Kindo and
M. Hagiwara, J. Phys. Soc. Jpn. 90, 044704/1-9 (2021).
22. †*Field-induced valence fluctuations in YbB12: R. Kurihara, A. Miyake, M. Tokunaga, A. Ikeda, Y. H. Matsuda,
A. Miyata, D. I. Gorbunov, T. Nomura, S. Zherlitsyn, J. Wosnitza and F. Iga, Phys. Rev. B 103, 115103 1-14 (2021).
23. †*Geometrical Hall effect and momentum-space Berry curvature from spin-reversed band pairs: M. Hirschberger,
Y. Nomura, H. Mitamura, A. Miyake, T. Koretsune, Y. Kaneko, L. Spitz, Y. Taguchi, A. Matsuo, K. Kindo, R. Arita,
M. Tokunaga and Y. Tokura, Phys. Rev. B 103, L041111(1-6) (2021).
24. †Martensitic Transformation and Metamagnetic Transition in Co-V-(Si, Al) Heusler Alloys: K. Nakamura, A. Miyake,
X. Xu, T. Omori, M. Tokunaga and R. Kainuma, Metals 11, 226/1-12 (2021).
25. †Observation of inverse magnetocaloric effect in magnetic-field-induced austenite phase of Heusler alloys
Ni50-xCoxMn31.5Ga18.5 (x = 9 and 9.7): T. Kihara, T. Roy, X. Xu, A. Miyake, M. Tsujikawa, H. Mitamura,
M. Tokunaga, Y. Adachi, T. Eto and T. Kanomata, Phys. Rev. Materials 5, 034416_1-13 (2021).
26. †Giant anomalous Hall effect from spin-chirality scattering in a chiral magnet: Y. Fujishiro, N. Kanazawa, R. Kurihara,
H. Ishizuka, T. Hori, F. S. Yasin, X. Yu, A. Tsukazaki, M. Ichikawa, M. Kawasaki, N. Nagaosa, M. Tokunaga andY. Tokura, Nat Commun 12, 317/1-6 (2021).

Y. Matsuda group
The magnetic-field-induced insulator to metal transition in W-doped VO2 has been discovered in 500 T using the electromagnetic flux compression ultrahigh magnetic field generator, The molecular orbital is destabilized by such a strong magnetic
field through the Pauli exclusion principle. This phenomenon can happen with the large spin Zeeman energy and the electronelectron correlation. In magnetic fields as high as 100 -200 T, we have investigated the magnon Bose-Einstein condensation in
TlCuCl3 and spin-state crystallization in LaCoO3. As for technical achievements, a measurement technique for electric resistivity and a method for boosting magnetic field have been developed. Also, we have proposed a combination of 100 T magnetic
fields and an intense x-ray by utilizing the single-turn coil method and the Japanese x-ray free electron laser SACLA. In
addition, cyclotron resonance in an InAs quantum well, temperature dependent magnetization process in YbB12, and magnetic
properties in Mn2V2O7 have been studied in high magnetic fields.
1.

†*Experimental measurements of effective mass in near-surface InAs quantum wells: J. Yuan, M. Hatefipour, B. A.

2.

†*Magnetization plateau observed by ultrahigh-field Faraday rotation in the kagome antiferromagnet herbertsmithite:

3.

Magill, W. Mayer, M. C. Dartiailh, K. Sardashti, K. S. Wickramasinghe, G. A. Khodaparast, Y. H. Matsuda, Y. Kohama,
Z. Yang, S. Thapa, C. J. Stanton and J. Shabani, Phys. Rev. B 101, 205310 1-8 (2020).
R. Okuma, D. Nakamura and S. Takeyama, Phys. Rev. B 102, 104429 1-4 (2020).

†Pressure and magnetic field effects on ferroelastic and antiferromagnetic orderings in honeycomb-lattice Mn V O :2 2 7

H. C. Wu, D. J. Hsieh, T. W. Yen, P. J. Sun, D. Chandrasekhar Kakarla, J. L. Her, Y. H. Matsuda, C. K. Chang, Y. C. Lai,
M. Gooch, L. Z. Deng, K. G. Webber, C. A. Lee, M. M. C. Chou, C. W. Chu and H. D. Yang, Phys. Rev. B 102, 075130
1-8 (2020).

4.

†*Quantum limit cyclotron resonance in monolayer epitaxial graphene in magnetic fields up to 560 T: The relativistic

5.

†*Particle-Hole Symmetry Breaking in a Spin-Dimer System TlCuCl Observed at 100 T: X. -G. Zhou, Y. Yao, Y. H.
3

6.

†Two Spin-State Crystallizations in LaCoO : A. Ikeda, Y. H. Matsuda and K. Sato, Phys. Rev. Lett. 125, 177202 1-6
3

7.

†The Temperature Dependence of the Magnetization Process of the Kondo Insulator YbB : Y. H. Matsuda, Y. Kakita
12electron and hole asymmetry: D. Nakamura, H. Saito, H. Hibino, K. Asano and S. Takeyama, Phys. Rev. B 101, 115420
1-5 (2020).
Matsuda, A. Ikeda, A. Matsuo, K. Kindo and H. Tanaka, Phys. Rev. Lett. 125, 267207 1-6 (2020).
(2020).

* Joint research among groups within ISSP.

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ISSP Activity Report 2020and F. Iga, Crystals 10, 26 1-7 (2020).
8.

†*Direct measurement of resistivity in destructive pulsed magnetic fields: Y. Kohama, F. Nabeshima, A. Maeda,

9.

†*Magnetic-field-induced insulator–metal transition in W-doped VO at 500 T: Y. H. Matsuda, D. Nakamura, A. Ikeda,
2
S. Takeyama, Y. Suga, H. Nakahara and Y. Muraoka, Nat Commun 11, 3591 1-7 (2020).

A. Ikeda and Y. H. Matsuda, Review of Scientific Instruments 91, 033901 1-5 (2020).

10. †*Single shot x-ray diffractometry in SACLA with pulsed magnetic fields up to 16 T: A. Ikeda, Y. H. Matsuda, X. Zhou,
T. Yajima, Y. Kubota, K. Tono and M. Yabashi, Phys. Rev. Research 2, 043175 1-6 (2020).
11. †*Field-induced valence fluctuations in YbB12: R. Kurihara, A. Miyake, M. Tokunaga, A. Ikeda, Y. H. Matsuda,
A. Miyata, D. I. Gorbunov, T. Nomura, S. Zherlitsyn, J. Wosnitza and F. Iga, Phys. Rev. B 103, 115103 1-14 (2021).
12. †*Higher magnetic-field generation by a mass-loaded single-turn coil: M. Gen, A. Ikeda, S. Kawachi, T. Shitaokoshi,
Y. H. Matsuda, Y. Kohama and T. Nomura, Review of Scientific Instruments 92, 033902 1-5 (2021).

Kohama group
In 2020, we have investigated high-field properties in many different systems, such as CeRhIn5, SrRuO3, CuInCr4S8, FeSe,
Ruby, High-Tc superconductor, and so on. We also developed the resistivity measurment technique for a research in ultra
high-magnetic fields above 100 T. The other technical developments including the super-capacitor driven pulsed magnet areunderway.
1.

†Symmetry Lowering on the Field-Induced Commensurate Phase in CeRhIn : T. Kanda, K. Arashima, Y. Hirose,52.

Electronic band structure of (111) SrRuO3 thin films: An angle-resolved photoemission spectroscopy study: H. Ryu,
Y. Ishida, B. Kim, J. R. Kim, W. J. Kim, Y. Kohama, S. Imajo, Z. Yang, W. Kyung, S. Hahn, B. Sohn, I. Song, M. Kim,
S. Huh, J. Jung, D. Kim, T. W. Noh, S. Das and C. Kim, Phys. Rev. B 102, 041102 (2020).

3.

*Enhanced spin correlations in the Bose-Einstein condensate compound Sr Cr O : T. Nomura, Y. Skourski, D. L.
3 2 8

4.

†*Experimental measurements of effective mass in near-surface InAs quantum wells: J. Yuan, M. Hatefipour, B. A.

5.

Magnetization process of the breathing pyrochlore magnet CuInCr4S8 in ultrahigh magnetic fields up to 150 T: M. Gen,Y. Okamato, M. Mori, K. Takenaka and Y. Kohama, Phys. Rev. B 101, 054434 (2020).

6.

*Observation of in-plane magnetic field induced phase transitions in FeSe: J. M. Ok, C. I. Kwon, Y. Kohama, J. S. You,

R. Settai, K. Matsui, T. Nomura, Y. Kohama and Y. Ihara, J. Phys. Soc. Jpn. 89, 094709 (2020).

Quintero-Castro, A. A. Zvyagin, A. V. Suslov, D. Gorbunov, S. Yasin, J. Wosnitza, K. Kindo, A. T. M. N. Islam, B. Lake,
Y. Kohama, S. Zherlitsyn and M. Jaime, Phys. Rev. B 102, 165144 (2020).
Magill, W. Mayer, M. C. Dartiailh, K. Sardashti, K. S. Wickramasinghe, G. A. Khodaparast, Y. H. Matsuda, Y. Kohama,
Z. Yang, S. Thapa, C. J. Stanton and J. Shabani, Phys. Rev. B 101, 205310 1-8 (2020).

S. K. Park, J.-H. Kim, Y. J. Jo, E. S. Choi, K. Kindo, W. Kang, K.-S. Kim, E. G. Moon, A. Gurevich and J. S. Kim,
Phys. Rev. B 101, 224509 (2020).

7.

*Quantum oscillations and magnetic field induced Fermi surface reconstruction in the charge density wave state of

8.

*Anisotropic Fully Gapped Superconductivity Possibly Mediated by Charge Fluctuations in a Nondimeric Organic

9.

*Observation of small Fermi pockets protected by clean CuO sheets of a high-Tc superconductor: S. Kunisada,2

A0.9Mo6O17 (A = Na, K): H. P. Zhu, M. Yang, J. Z. Ke, H. K. Zuo, T. Peng, J. F. Wang, Y. Liu, X. Xu, Y. Kohama,
K. Kindo and M. Greenblatt, Phys. Rev. B 102, 235164 (2020).
Complex: S. Imajo, H. Akutsu, R. Kurihara, T. Yajima, Y. Kohama, M. Tokunaga, K. Kindo and Y. Nakazawa, Phys.
Rev. Lett. 125, 177002 (2020).

S. Isono, Y. Kohama, S. Sakai, C. Bareille, S. Sakuragi, R. Noguchi, K. Kurokawa, K. Kuroda, Y. Ishida, S. Adachi,
R. Sekine, T. K. Kim, C. Cacho, S. Shin, T. Tohyama, K. Tokiwa and T. Kondo, Science 369, 833 (2020).

10. *Extracting the Chiral Contribution to the Negative Longitudinal Magnetoresistance in Epitaxial Pr2Ir2O7 Thin Films:
T. Ohtsuki, Z. Tian, A. Endo, M. Halim, S. Katsumoto, Y. Kohama, K. Kindo, M. Lippmaa and S. Nakatsuji, JPS Conf.
Proc. 30, 011181 (1-6) (2020).
11. Strain engineering of the magnetic multipole moments and anomalous Hall effect in pyrochlore iridate thin films: W. J.
Kim, T. Oh, J. Song, E. K. Ko, Y. Li, J. Mun, B. Kim, J. Son, Z. Yang, Y. Kohama, M. Kim, B.-J. Yang and T. W. Noh,Sci. Adv. 6, eabb1539 (2020).
12. †*Direct measurement of resistivity in destructive pulsed magnetic fields: Y. Kohama, F. Nabeshima, A. Maeda,† Joint research with outside partners.

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187

A. Ikeda and Y. H. Matsuda, Review of Scientific Instruments 91, 033901 1-5 (2020).
13. Angle dependence of Hc2 with a crossover between the orbital and paramagnetic limits: H. Matsuoka, M. Nakano,T. Shitaokoshi, Y. Wang, Y. Kashiwabara, S. Yoshida, Y. Kohama, T. Ouchi, K. Ishizaka, M. Kawasaki, T. Nojima andY. Iwasa, Phys. Rev. Research 2, 012064(R) (2020).
14. Crystal-field Paschen-Back effect on ruby in ultrahigh magnetic fields: M. Gen, T. Kanda, T. Shitaokoshi, Y. Kohama
and T. Nomura, Phys. Rev. Research 2, 033257 (2020).
15. Van der Waals SnSe2(1−x)S2x Alloys: Composition-Dependent Bowing Coefficient and Electron–Phonon Interaction:
Z. R. Kudrynskyi, X. Wang, J. Sutcliffe, M. A. Bhuiyan, Y. Fu, Z. Yang, O. Makarovsky, L. Eaves, A. Solomon, V. T.
Maslyuk, Z. D. Kovalyuk, L. Zhang and A. Patanè, Advanced Functional Materials 30, 1908092 (2020).
16. Broad Tunability of Carrier Effective Masses in Two-Dimensional Halide Perovskites: M. Dyksik, H. Duim, X. Zhu,
Z. Yang, M. Gen, Y. Kohama, S. Adjokatse, D. K. Maude, M. A. Loi, D. A. Egger, M. Baranowski and P. Plochocka,
ACS Energy Lett. 5, 3609 (2020).
17. *High-field phase diagram of Ni3V2O8 studied by specific heat and magnetocaloric effect measurements: C. Dong,
Y. Kohama, Z. Z. He, X. T. Han, K. Sato, A. Matsuo, K. Kindo, M. Yang and J. F. Wang, J. Phys.: Condens. Matter 33,
205402 (2021).
18. Emergence of Frustrated Short-Range Order above Long-Range Order in the S = 1/2 Kagome Antiferromagnet
CaCu3(OD)6Cl2・0.6D2O: Y. Ihara, K. Matsui, Y. Kohama, S. Luther, D. Opherden, J. Wosnitza, H. Kühne and H. K.
Yoshida, J. Phys. Soc. Jpn. 90, 023703 (2021).
19. Element-specific field-induced spin reorientation and tetracritical point in MnCr2S4: Sh. Yamamoto, H. Suwa,
T. Kihara, T. Nomura, Y. Kotani, T. Nakamura, Y. Skourski, S. Zherlitsyn, L. Prodan, V. Tsurkan, H. Nojiri, A. Loidl andJ. Wosnitza, Phys. Rev. B 103, L020408 (2021).
20. Wide Critical Fluctuations of the Field-Induced Phase Transition in Graphite: C. Marcenat, T. Klein, D. LeBoeuf,
A. Jaoui, G. Seyfarth, J. Kacmarcik, Y. Kohama, H. Cercellier, H. Aubin, K. Behnia and B. Fauque, Phys. Rev. Lett.
126, 106801 (2021).
21. *Compact megajoule-class pulsed power supply for generating long-pulsed magnetic fields: K. Matsui, T. Kanda,
Y. Ihara, K. Kindo and Y. Kohama, Review of Scientific Instruments 92, 024711 (2021).
22. †*Higher magnetic-field generation by a mass-loaded single-turn coil: M. Gen, A. Ikeda, S. Kawachi, T. Shitaokoshi,
Y. H. Matsuda, Y. Kohama and T. Nomura, Review of Scientific Instruments 92, 033902 1-5 (2021).
23. *High-resolution calorimetry in pulsed magnetic fields: S. Imajo, C. Dong, A. Matsuo, K. Kindo and Y. Kohama,
Review of Scientific Instruments 92, 043901 (2021).

Center of Computational Materials Science
Akai team
The main objective of is to predict/discover new functionality materials by means of computational materials design (CMD). In
particular, new high-performance permanent magnets is one of main targets. Developments of new methods of quantum simulation are also important themes. Our activities include the followings: (1) A method that enabled us to treat low energy collective excitations, phonons and magnons, in the framework of first-principles KKR-CPA was developed and applied to various
magnetic systems. The effects of these excitations on magnetization at finite temperature and the Curie temperature of typicalmagnetic systems, including bcc Fe and permanent-magnet materials B2(Fe, Co)14B, were calculated using low energy effective
Hamiltonian obtained by a first-principles KKR-Green's function method where the magnons and phonons were included in astatic and local scheme. The effects of these excitations were important in determining the magnetic properties, was concluded;(2) The magnetic Friedel oscillation near the surface of Fe films was detected layer by layer measurement using synchrotron
Mössbauer source. The behavior was well reproduced by the hyperfine interactions calculated using the full-potential KKR
method and the KKR method combined the optimized effective potential (OEP) method; (3) An efficient method to calculate
spin-wave dispersions using the low-energy effective Hamiltonian derived from first-principles calculations was developed andapplied to rare-earth based permanent magnet materials including R2(Fe, Co)14B; (4) A search for rare-earth bases permanent
magnets materials of better performance at finite temperature were made using massive data obtained as results of first-principles KKR-CPA together with fairly large number of experimental data by a newly developed data assimilation technique. The
method developed was proven powerful enough to predict possible candidates for compositions of high-performance permanent
magnet materials.
* Joint research among groups within ISSP.

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1.

Calculating Curie temperatures for rare-earth permanent magnets: Ab initio inspection of localized magnetic moments ind-electron ferromagnetism: M. Matsumoto and H. Akai, Phys. Rev. B 101, 144402 (2020).

2.

Element- and orbital-selective magnetic coherent rotation at the first-order phase transition of a hard uniaxial ferrimagnet: Sh. Yamamoto, D. I. Gorbunov, H. Akai, H. Yasumura, Y. Kotani, T. Nakamura, T. Kato, N. V. Mushnikov,
A. V. Andreev, H. Nojiri and J. Wosnitza, Phys. Rev. B 101, 174430 (2020).

3.

Magnetic Friedel Oscillation at the Fe(001) Surface: Direct Observation by Atomic-Layer-Resolved Synchrotron Radiation 57Fe Mössbauer Spectroscopy: T. Mitsui, S. Sakai, S. Li, T. Ueno, T. Watanuki, Y. Kobayashi, R. Masuda, M. Setoand H. Akai, Phys. Rev. Lett. 125, 236806 (2020).

4.

*First-principles calculations of finite temperature electronic structures and transport properties of Heusler alloy

5.

Spin-wave dispersion and exchange stiffness in Nd2Fe14B and RFe11Ti (R=Y, Nd, Sm) from first-principles calculations: T. Fukazawa, H. Akai, Y. Harashima and T. Miyake, Phys. Rev. B 103, 024418-1–7 (2021).

6.

Data assimilation method for experimental and first-principles data: Finite-temperature magnetization of (Nd, Pr, La,
Ce)2(Fe, Co, Ni)14B: Y. Harashima, K. Tamai, S. Doi, M. Matsumoto, H. Akai, N. Kawashima, M. Ito, N. Sakuma,
A. Kato, T. Shoji and T. Miyake, Phys. Rev. Materials 5, 013806-1–10 (2021).

Co2MnSi: H. Shinya, S. Kou, T. Fukushima, A. Masago, K. Sato, H. Katayama-Yoshida and H. Akai, Appl. Phys. Lett.
117, 042402(1-5) (2020).

Miyashita team
We studied temperature dependence of coercivity for permanent magnets as the activity of ESICMM. We also studied subjects
for phase transitions and quantum dynamics.
1.

Dynamical aspects of magnetization reversal in the neodymium permanent magnet by a stochastic Landau-LifshitzGilbert simulation at finite temperature: Real-time dynamics and quantitative estimation of coercive force: M. Nishino,
I. E. Uysal, T. Hinokihara and S. Miyashita, Phys. Rev. B 102, 020413(R) (1-5) (2020).

2.

Elastic-frustration-driven unusual magnetoelastic properties in a switchable core-shell spin-crossover nanostructure:
Y. Singh, H. Oubouchou, M. Nishino, S. Miyashita and K. Boukheddaden, Phys. Rev. B 101, 054105(1-15) (2020).

3.

Magnetic field threshold for nucleation and depinning of domain walls in the neodymium permanent magnet Nd2Fe14B:
I. E. Uysal, M. Nishino and S. Miyashita, Phys. Rev. B 101, 094421 (1-9) (2020).

4.

Dynamical phase transition in Floquet optical bistable systems: An approach from finite-size quantum systems:
T. Shirai, S. Todo and S. Miyashita, Phys. Rev. E 101, 013809(1-7) (2020).

5.

Magnetic-Pole Flip by Millimeter Wave: S.-I. Ohkoshi, M. Yoshikiyo, K. Imoto, K. Nakagawa, A. Namai, H. Tokoro,
Y. Yahagi, K. Takeuchi, F. Jia, S. Miyashita, M. Nakajima, H. Qiu, K. Kato, T. Yamaoka, M. Shirata, K. Naoi,
K. Yagishita and H. Doshita, Adv. Mater. 32, 2004897(1-7) (2020).

6.

Construction of quantum dark soliton in onedimensional Bose gas: E. Kaminishi, T. Mori and S. Miyashita, J. Phys. B:
At. Mol. Opt. Phys. 53, 095302(1-8) (2020).

7.

Role of atomic-scale thermal fluctuations in the coercivity: Y. Toga, S. Miyashita, A. Sakuma and T. Miyake, npj
Computational Materials 6:67, 1-7 (2020).

8.

Effect of the surface magnetic anisotropy of neodymium atoms on the coercivity in neodymium permanent magnets:
M. Nishino, I. E. Uysal and S. Miyashita, Phys. Rev. B 103, 014418(1-9) (2021).

9.

Systematic survey of magnetic configurations in multilayer ferromagnet system with dipole-dipole interaction:
T. Hinokihara and S. Miyashita, Phys. Rev. B 103, 054421(1-9) (2021).

10. Rapid Faraday Rotation on epsilon-Iron Oxide Magnetic Nanoparticles by Visible and Terahertz Pulsed Light: S.-I.
Ohkoshi, K. Imoto, A. Namai, M. Yoshikiyo, S. Miyashita, H. Qiu, S. Kimoto, K. Kato and M. Nakajima, J. Am. Chem.
Soc. 141, 1775-1780 (2021).

† Joint research with outside partners.

ISSP Activity Report 2020

189

Laser and Synchrotron Research Center
Kobayashi group
We have supplied some laser systems for applications such as astronomical science and photoemission spectroscopy. Some
results related to a laser processing were published in 2020.
1.

†Ablation threshold and crater morphology of amorphous and crystalline SiO glass for extreme ultraviolet femto22.

†Precision measurement of ablation thresholds with variable pulse duration laser: T. Takahashi, S. Tani, R. Kuroda and3.

†Study on nonthermal–thermal processing boundary in drilling of ceramics using ultrashort pulse laser system withsecond pulses: T. Shibuya, K. Sakaue, H. Ogawa, T. -H. Dinh, D. Satoh, E. Terasawa, M. Washio, M. Tanaka,
T. Higashiguchi, M. Ishino, Y. Kubota, Y. Inubushi, S. Owada, M. Nishikino, Y. Kobayashi and R. Kuroda, Jpn. J. Appl.
Phys. 59, 122004 (2020).
Y. Kobayashi, Appl. Phys. A 126, 582 (2020).

variable parameters over a wide range: A. Narazaki, H. Takada, D. Yoshitomi, K. Torizuka and Y. Kobayashi, Appl.
Phys. A 126, 252 (2020).

4. レーザーアブレーションの学理解明と次世代レーザー加工に向けた自動計測技術開発 : 小林 洋平 , 高橋 孝 , 谷峻 太郎 ,応用物理 , Vol.89, No.12, 719-723 (2020).
5.

Q-switching stability limits of Kerr-lens mode locking: S. Kimura, S. Tani and Y. Kobayashi, Phys. Rev. A 102, 043505(2020).

6.

Neural-network-assisted in situ processing monitoring by speckle pattern observation: S. Tani, Y. Aoyagi and
Y. Kobayashi, Opt. Express 28, 26180 (2020).

7.

Piezo-electric transducer actuated mirror with a servo bandwidth beyond 500 kHz: T. Nakamura, S. Tani, I. Ito, M. Endoand Y. Kobayashi, Opt. Express 28, 16118 (2020).

8.

†Work function seen with sub-meV precision through laser photoemission: Y. Ishida, J. K. Jung, M. S. Kim, J. Kwon,

9.

Subgigahertz-resolution table-top spectrograph calibrated with a 4-GHz optical frequency comb: M. Endo,T. Sukegawa, A. Silva and Y. Kobayashi, J. Astron. Telesc. Instrum. Syst. 6, 1 (2020).

Y. S. Kim, D. Chung, I. Song, C. Kim, T. Otsu and Y. Kobayashi, Commun Phys 3, 158 (2020).

10. †Ablation thresholds and morphological changes of poly-L-lactic acid for pulse durations in the femtosecond-topicosecond regime: T. Shibuya, D. Yoshitomi, D. Satoh, K. Sakaue, M. Tanaka, H. Takada, H. Ogawa, K. Torizuka,
Y. Kobayashi and R. Kuroda, Surf Interface Anal 52, 1145 (2020).
11. 固体レーザーによる光周波数コム : 小林 洋平 , 木村 祥太 , 電子情報通信学会誌 , Vol.103, No.11, 1082, 1088 (2020).
12. *Direct generation of sub-picosecond pulse via multi-section gain switching: T. Nakamura, T. Ito, H. Nakamae, C. Kim,
Y. Hazama, Y. Kobayashi, R. Kuroda and H. Akiyama, Opt. Lett. 46, 1277 (2021).
13. Coherent control of acoustic phonons in a silica fiber using a multi-GHz optical frequency comb: M. Endo, S. Kimura,
S. Tani and Y. Kobayashi, Commun Phys 4, 73 (2021).
14. †Ultrafast laser processing of ceramics: Comprehensive survey of laser parameters: A. Narazaki, H. Takada, D. Yoshitomi, K. Torizuka and Y. Kobayashi, Journal of Laser Applications 33, 012009 (2021).

Harada group
This year, in order to tackle the new coronavirus problem, we analyzed water treatment membranes that can be used as virus
removal membranes as part of the project to analyze the solid-liquid interface, which is the main theme of Grant-in-Aid for
Scientific Research on Innovative Areas "Aquatic Functional Materials". With the support of the AMED project "Developmentof Technology for Countermeasures against Infectious Diseases including Viruses," we also promoted research and developmenton the improvement of coating materials for the inner wall of the tubes for Extra Corporeal Membrane Oxygenation (ECMO),
which is mainly used in the treatment of patients with severe pneumonia. In order to develop cathode materials that contributeto the high performance of lithium-ion batteries, we analyzed materials in which the ligand oxygen, rather than transition
metals, is involved in the redox reaction. We succeeded in capturing the dimerization of oxygen atoms interacting with metals
under high potentials using RIXS.
1.

†Revisiting the Phase Diagram of T*-type La
1−x/2Eu1−x/2SrxCuO4 Using Oxygen K-edge X-ray Absorption Spectroscopy: S. Asano, K. Ishii, K. Yamagami, J. Miyawaki, Y. Harada and M. Fujita, J. Phys. Soc. Jpn. 89, 075002 (1-2)* Joint research among groups within ISSP.

190

ISSP Activity Report 2020

(2020).
2.

†*Localized character of charge excitations for La
2−xSrxNiO4+δ revealed by oxygen K-edge resonant inelastic x-ray

3.

†Anisotropic X-Ray Scattering of Transiently Oriented Water: K. H. Kim, A. Späh, H. Pathak, C. Yang, S. Bonetti, K.

4.

†Ion Selectivity of Water Molecules in Subnanoporous Liquid-Crystalline Water-Treatment Membranes: A Structural

5.

†Tetragonal Distortion of a BaTiO /Bi Na TiO Nanocomposite Responsible for Anomalous Piezoelectric and Ferro3
0.5
0.5
3

6.

†Multiorbital bond formation for stable oxygen-redox reaction in battery electrodes: T. Sudayama, K. Uehara, T. Mukai,

scattering: K. Yamagami, K. Ishii, Y. Hirata, K. Ikeda, J. Miyawaki, Y. Harada, M. Miyazaki, S. Asano, M. Fujita andH. Wadati, Phys. Rev. B 102, 165145 (1-7) (2020).
Amann-Winkel, D. Mariedahl, D. Schlesinger, J. A. Sellberg, D. Mendez, G. van der Schot, H. Y. Hwang, J. Clark, O.
Shigeki, T. Tadashi, Y. Harada, H. Ogasawara, T. Katayama, A. Nilsson and F. Perakis, Phys. Rev. Lett. 125, 076002(1-6) (2020).
Study of Hydrogen Bonding: R. Watanabe, T. Sakamoto, K. Yamazoe, J. Miyawaki, T. Kato and Y. Harada, Angew.
Chem. Int. Ed. 59, 23461-23465 (2020).

electric Behaviors: W. Zhang, Q. Feng, E. Hosono, D. Asakura, J. Miyawaki and Y. Harada, ACS Omega 5, 2280022807 (2020).

D. Asakura, X.-M. Shi, A. Tsuchimoto, B. M. D. Boisse, T. Shimada, E. Watanabe, Y. Harada, M. Nakayama, M. Okubo
and A. Yamada, Energy Environ. Sci. 13, 1492-1500 (2020).

I. Matsuda group
Since the beginning of the year 2020, there has been a serious coronavirus (COVID-19) pandemic over the world and carehas been urgently needed for those affected. In living, we have had to stop the spread of the virus by avoiding three Cs: closed
spaces, crowded places, and close contact. No exception has been applied for experiments in any facilities or laboratories,
including our beamline, SPring-8 BL07LSU. A number of the user-group members and visiting itself have been restricted. After
summer, beamtime experiments were carried out normally for domestic users. We have made advanced X-ray magneto-opticalexperiments of exotic quantum phases and ambient pressure photoemission measurements on surface reactions. In the laboratory, soft X-ray non-linear optical research was made at X-ray free electron laser facility at SACLA.
1.

Topological Dirac nodal loops in nonsymmorphic hydrogenated monolayer boron: N. T. Cuong, I. Tateishi, M. Cameau,
M. Niibe, N. Umezawa, B. Slater, K. Yubuta, T. Kondo, M. Ogata, S. Okada and I. Matsuda, Phys. Rev. B 101, 195412(2020).

2.

Two-dimensional conducting layer on SrTiO3 surface induced by hydrogenation: Y. Takeuchi, R. Hobara, R. Akiyama,
A. Takayama, S. Ichinokura, R. Yukawa, I. Matsuda and S. Hasegawa, Phys. Rev. B 101, 085422-1,-6 (2020).

3.

†Time-resolved X-ray photoelectron diffraction using an angle-resolved time-of-flight electron analyzer: A. K. R. Ang,

4.

*Element-selectively tracking ultrafast demagnetization process in Co/Pt multilayer thin films by the resonant magneto-

Y. Fukatsu, K. Kimura, Y. Yamamoto, T. Yonezawa, H. Nitta, A. Fleurence, S. Yamamoto, I. Matsuda, Y. YamadaTakamura and K. Hayashi, Jpn. J. Appl. Phys. 59, 100902 (2020).
optical Kerr effect: K. Yamamoto, S. E. Moussaoui, Y. Hirata, S. Yamamoto, Y. Kubota, S. Owada, M. Yabashi, T. Seki,
K. Takanashi, I. Matsuda and H. Wadati, Appl. Phys. Lett. 116, 172406-1,-5 (2020).

5.

Scanning magneto-optical Kerr effect (MOKE) measurement with element-selectivity by using a soft x-ray freeelectron laser and an ellipsoidal mirror: Y. Kubota, H. Motoyama, G. Yamaguchi, S. Egawa, Y. Takeo, M. Mizuguchi,
H. Sharma, S. Owada, K. Tono, H. Mimura, I. Matsuda and M. Yabashi, Appl. Phys. Lett. 117, 042405 (2020).

6.

*A computational examination of the electric-field-induced proton transfer along the interface hydrogen bond between

7.

分割型アンジェレータを用いた新しい軟 X 線磁気光学法と次世代光源への展開 : 久保田 雄也 , 松田 巌 , 放射光 33,

8.

†*Atomistic-Level Description of GaN/Water Interface by a Combined Spectroscopic and First-Principles Computational Approach: M. Sato, Y. Imazeki, T. Takeda, M. Kobayashi, S. Yamamoto, I. Matsuda, J. Yoshinobu, Y. Nakano and
M. Sugiyama, J. Phys. Chem. C 124, 12466 (2020).

9.

*Edge-state correlation accelerates metal-insulator transition in topological semimetal nanofilms: S. Ito, M. Arita,

proton donating and accepting self-assembled monolayers: Y. Kanematsu, H. S. Kato, S. Yoshimoto, A. Ueda,
S. Yamamoto, H. Mori, J. Yoshinobu, I. Matsuda and M. Tachikawa, Chem. Phys. Lett. 741, 137091 (2020).
206-212 (2020).

J. Haruyama, B. Feng, W. -C. Chen, H. Namatame, M. Taniguchi, C. -M. Cheng, G. Bian, S. -J. Tang, T. -C. Chiang,
O. Sugino, F. Komori and I. Matsuda, Science Advances 6, eaaz5015 (7 pages) (2020).
† Joint research with outside partners.

ISSP Activity Report 2020191

10. *Electronic structure of a (3×3)-ordered silicon layer on Al(111): Y. Sato, Y. Fukaya, M. Cameau, A. K. Kundu,
D. Shiga, R. Yukawa, K. Horiba, C.-H. Chen, A. Huang, H.-T. Jeng, T. Ozaki, H. Kumigashira, M. Niibe and
I. Matsuda, Phys. Rev. Materials 4, 064005 (2020).
11. Ellipsometer Equipped with Multiple Mirrors for Element-selective Soft X-ray Experiments: M. Araki, J. Meikaku,
Y. Kubota, J. Miyawaki, Y. Kosegawa, S. E. Moussaoui, T. Bouillaud, P. Manset, S. Owada, K. Tono, M. Yabashi and
I. Matsuda, e-J. Surf. Sci. Nanotechnol. 18, 231 (2020).
12. Geometrical Frustration of B-H Bonds in Layered Hydrogen Borides Accessible by Soft Chemistry: S. Tominaka,
R. Ishibiki, A. Fujino, K. Kawakami, K. Ohara, I. Matsuda, H. Hosono and T. Kondo, Chem 6, 406-418 (2020).
13. Recent progresses in spectroscopies using soft X-ray free-electron laser: I. Matsuda and Y. Kubota, Chem. Lett.
Advanced publication, cl.200881 (2021).
14. †*Femtosecond Charge Density Modulations in Photoexcited CuWO4: Y. Uemura, A. S. M. Ismail, S. H. Park,
S. Kwon, M. Kim, Y. Niwa, H. Wadati, H. Elnaggar, F. Frati, T. Haarman, N. Höppel, N. Huse, Y. Hirata, Y. Zhang,
K. Yamagami, S. Yamamoto, I. Matsuda, T. Katayama, T. Togashi, S. Owada, M. Yabashi, U. Halisdemir, G. Koster,T. Yokoyama, B. M. Weckhuysen and F. M. F. D. Groot, J. Phys. Chem. C 125, 7329 (2021).
15. †Valence Fluctuations in Yb(Al,Fe)B4 Studied by Nanosecond-time-resolved Photoemission Spectroscopy Using
Synchrotron Radiation: M. Okawa, K. Akikubo, S. Yamamoto, I. Matsuda and T. Saitoh, e-J. Surf. Sci. Nanotechnol. 19,
20 (2021).

Itatani group
We mainly worked on soft-X-ray attosecond spectroscopy and the upgrade of the attosecond beamline. First, we extended thenitrogen K-edge experiments from diatomic molecules (NO) to triatomic molecules (N2O) and observed intriguing dynamicsof 2ω oscillation. The interpretation of this ultrafast oscillation is underway. Second, a new sample-feeding system for organic
molecules was introduced. We successfully measured static absorption spectra of benzene, acetone, ethanol, and methanol at
the carbon K edge around 280 eV. Third, a new soft X-ray spectrometer was developed and installed to improve the energy
resolution. In addition, we started to develop new infrastructures in the building E. We constructed a beamline booth next tothe existing laser booth, with a clean and temperature-stable environment for ultrafast experiments using EUV and soft-X-ray
pulses. A Ti:sapphire laser system was developed as a pump source for an ultrashort-pulse infrared optical parametric chirped
pulse amplifier (OPCPA), or as a driver to produce high-flux femtosecond EUV pulses for imaging experiments. We also
developed prototype light sources such as a mid-infrared optical parametric amplifier (OPA) and a harmonic-based tunable UV
source, both of which are pumped by a high-repetition-rate Yb laser.
1.

†*Photoinduced Phase Transition from Excitonic Insulator to Semimetal-like State in Ta Ni
2 1−xCoxSe5(x = 0.10):2.

†Detecting

3.

*Efficient Terahertz Harmonic Generation with Coherent Acceleration of Electrons in the Dirac Semimetal Cd As :3 2

4.

軟 X 線領域でのアト秒分光 : 斎藤 成之 , 光学 49, 249 (2020).

5.

中赤外光パルスを用いた固体高次高調波発生とその偏光特性 : 石井 順久 , 金島 圭佑 , 夏 沛宇 , 斎藤 成之 , 金井 輝人 ,板谷 治郎 , レーザー研究 49, 168-173 (2020).

6.

†Role of virtual band population for high harmonic generation in solids: Y. Sanari, H. Hirori, T. Aharen, H. Tahara,

7.

†Observation of the quantum shift of a backward rescattering caustic by carrier-envelope phase mapping: T. Mizuno,

8.

*Optical parametric amplification of phase-stable terahertz-to-mid-infrared pulses studied in the time domain: N. Kanda,

9.

†Time-domain spectroscopy of optical parametric amplification for phase-stable terahertz-to-midinfrared pulses:

T. Mitsuoka, T. Suzuki, H. Takagi, N. Katayama, H. Sawa, M. Nohara, M. Watanabe, J. Xu, Q. Ren, M. Fujisawa,T. Kanai, J. Itatani, S. Shin, K. Okazaki and T. Mizokawa, J. Phys. Soc. Jpn. 89, 124703 (2020).
electron-phonon coupling during photoinduced phase transition,: T. Suzuki, Y. Shinohara, Y. Lu,
M. Watanabe, J. Xu, K. L. Ishikawa, H. Takagi, M. Nohara, N. Katayama, H. Sawa, M. Fujisawa, T. Kanai, J. Itatani,
T. Mizokawa, S. Shin and K. Okazaki, Phys. Rev. B 103, L121105 (2020).
B. Cheng, N. Kanda, T. N. Ikeda, T. Matsuda, P. Xia, T. Schumann, S. Stemmer, J. Itatani, N. P. Armitage and R. Matsunaga, Phys. Rev. Lett. 124, 117402 (2020).

Y. Shinohara, K. L. Ishikawa, T. Otobe, P. Xia, N. Ishii, J. Itatani, S. A. Sato and Y. Kanemitsu, Phys. Rev. B (Rapid
Communication) 102, 041125(R)-1-7 (2020).

N. Ishii, T. Kanai, P. Rosenberger, D. Zietlow, M. F. Kling, O. I. Tolstikhin, T. Morishita and J. Itatani, Phys. Rev. A 103,
043121 (2021).
N. Ishii, J. Itatani and R. Matsunaga, Optics Express 29, 3479-3489 (2021).

* Joint research among groups within ISSP.

192

ISSP Activity Report 2020

N. Kanda, N. Ishii, J. Itatani and R. Matsunaga, Optics Express 29(3), 3479-3489 (2021).

Kondo group
We use angle-resolved photoemission spectroscopy (ARPES) with ultrahigh energy resolution. The main findings in 2020 were
small pockets in cuprate, Devil's staircase in CeSb, and spin-polarized band in Te.
1.

†*Bulk quantum Hall effect of spin-valley coupled Dirac fermions in the polar antiferromagnet BaMnSb2: H. Sakai,

2.

Three-dimensional electronic structure in ferromagnetic Fe3Sn2 with breathing kagome bilayers: H. Tanaka,
Y. Fujisawa, K. Kuroda, R. Noguchi, S. Sakuragi, C. Bareille, B. Smith, C. Cacho, S. W. Jung, T. Muro, Y. Okada andT. Kondo, Phys. Rev. B 101, 161114 (2020).

3.

*Radial Spin Texture in Elemental Tellurium with Chiral Crystal Structure: M. Sakano, M. Hirayama, T. Takahashi,

4.

*Observation of small Fermi pockets protected by clean CuO sheets of a high-Tc superconductor: S. Kunisada,
2

5.

*Devil's staircase transition of the electronic structures in CeSb: K. Kuroda, Y. Arai, N. Rezaei, S. Kunisada,

6.

*Observation and control of the weak topological insulator state in ZrTe : P. Zhang, R. Noguchi, K. Kuroda, C. Lin, K.
5

H. Fujimura, S. Sakuragi, M. Ochi, R. Kurihara, A. Miyake, M. Tokunaga, T. Kojima, D. Hashizume, T. Muro,
K. Kuroda, T. Kondo, T. Kida, M. Hagiwara, K. Kuroki, M. Kondo, K. Tsuruda, H. Murakawa and N. Hanasaki, Phys.
Rev. B 101, 081104/1-7 (2020).

S. Akebi, M. Nakayama, K. Kuroda, K. Taguchi, T. Yoshikawa, K. Miyamoto, T. Okuda, K. Ono, H. Kumigashira,T. Ideue, Y. Iwasa, N. Mitsuishi, K. Ishizaka, S. Shin, T. Miyake, S. Murakami, T. Sasagawa and T. Kondo, Phys. Rev.
Lett. 124, 136404 (2020).
S. Isono, Y. Kohama, S. Sakai, C. Bareille, S. Sakuragi, R. Noguchi, K. Kurokawa, K. Kuroda, Y. Ishida, S. Adachi,
R. Sekine, T. K. Kim, C. Cacho, S. Shin, T. Tohyama, K. Tokiwa and T. Kondo, Science 369, 833 (2020).
S. Sakuragi, M. Alaei, Y. Kinoshita, C. Bareille, R. Noguchi, M. Nakayama, S. Akebi, M. Sakano, K. Kawaguchi,
M. Arita, S. Ideta, K. Tanaka, H. Kitazawa, K. Okazaki, M. Tokunaga, Y. Haga, S. Shin, H. S. Suzuki, R. Arita andT. Kondo, Nat Commun 11, 2888/1-9 (2020).
Kawaguchi, K. Yaji, A. Harasawa, M. Lippmaa, S. Nie, H. Weng, V. Kandyba, A. Giampietri, A. Barinov, Q. Li, G. D.
Gu, S. Shin and T. Kondo, Nat. Commun. 12, 406 (2021).

Matsunaga group
We have investigated light-matter interactions and light-induced nonequilibrium phenomena in solids by utilizing terahertz(THz) pulse. We have studied nonlinear THz responses and nonequilibrium dynamics of carries in Dirac and Weyl semimetals.
We have also developed optical parametric amplification of low-frequency infrared pulses in the intermediate region between
THz frequency and mid-infrared, 167., from 16.9 to 44.8 THz (6.7–17.8 μm) based on the intra-pulse differential frequency
generation in GaSe. The long-term phase drift of the THz-to-MIR pulses after two-stage OPA is as small as 16 mrad during a
6-h operation without any active feedback. Our scheme using the intra-pulse DFG and post-amplification proposes a new route
to intense THz-to-MIR light sources with extreme phase stability.
1.

*Efficient Terahertz Harmonic Generation with Coherent Acceleration of Electrons in the Dirac Semimetal Cd As :3 2

2.

*Room-temperature terahertz anomalous Hall effect in Weyl antiferromagnet Mn Sn thin films: T. Matsuda, N. Kanda,
33.

Opening a new route to multiport coherent XUV sources via intracavity high-order harmonic generation: N. Kanda,
T. Imahoko, K. Yoshida, A. Tanabashi, A. Amani Eilanlou, Y. Nabekawa, T. Sumiyoshi, M. Kuwata-Gonokami and
K. Midorikawa, Light: Sci. Appl. 9, 168 (2020).

4.

*Optical parametric amplification of phase-stable terahertz-to-mid-infrared pulses studied in the time domain: N. Kanda,

B. Cheng, N. Kanda, T. N. Ikeda, T. Matsuda, P. Xia, T. Schumann, S. Stemmer, J. Itatani, N. P. Armitage and R. Matsunaga, Phys. Rev. Lett. 124, 117402 (2020).
T. Higo, N. P. Armitage, S. Nakatsuji and R. Matsunaga, Nat Commun 11, 909 (2020).

N. Ishii, J. Itatani and R. Matsunaga, Optics Express 29, 3479-3489 (2021).

Okazaki group
We have investigated superconducting-gap structures of unconventional superconductors by a low-temperature and highresolution laser ARPES apparatus and transient electronic structures in photo-excited non-equilibrium states by a time-resolved
ARPES apparatus using EUV and SX lasers. In the academic year 2020, we have found that Bose–Einstein condensation (BEC)
superconductivity is induced by disappearance of the nematic state in FeSe by high-resolution laser ARPES. In addition, we† Joint research with outside partners.

ISSP Activity Report 2020193

have revealed a characteristic electron-phonon coupling during the photo-induced insulator-to-metal transition in Ta2NiSe5 by
a newly developed analysis method, frequency-domain angle-resolved photoemission spectroscopy (FDARPES), based on themeasurements of HHG laser time-resolved ARPES.
1.

†*Photoinduced Phase Transition from Excitonic Insulator to Semimetal-like State in Ta Ni
2 1−xCoxSe5(x = 0.10):

2.

Massive Suppression of Proximity Pairing in Topological (Bi1-xSbx)2Te3 Films on Niobium: J. A. Hlevyack,S. Najafzadeh, M. -K. Lin, T. Hashimoto, T. Nagashima, A. Tsuzuki, A. Fukushima, C. Bareille, Y. Bai, P. Chen, R. -Y.
Liu, Y. Li, D. Fl"ototto, J. Avila, J. N. Eckstein, S. Shin, K. Okazaki and T. -C. Chiang, Phys. Rev. Lett. 124, 236402(2020).

3.

Bose-Einstein condensation superconductivity induced by disappearance of the nematic state: T. Hashimoto, Y. Ota,
A. Tsuzuki, T. Nagashima, A. Fukushima, S. Kasahara, Y. Matsuda, K. Matsuura, Y. Mizukami, T. Shibauchi, S. Shinand K. Okazaki, Sci. Adv. 6, eabb9052 (2020).

4.

*Devil's staircase transition of the electronic structures in CeSb: K. Kuroda, Y. Arai, N. Rezaei, S. Kunisada,

5.

*Detecting

T. Mitsuoka, T. Suzuki, H. Takagi, N. Katayama, H. Sawa, M. Nohara, M. Watanabe, J. Xu, Q. Ren, M. Fujisawa,T. Kanai, J. Itatani, S. Shin, K. Okazaki and T. Mizokawa, J. Phys. Soc. Jpn. 89, 124703 (2020).

S. Sakuragi, M. Alaei, Y. Kinoshita, C. Bareille, R. Noguchi, M. Nakayama, S. Akebi, M. Sakano, K. Kawaguchi,
M. Arita, S. Ideta, K. Tanaka, H. Kitazawa, K. Okazaki, M. Tokunaga, Y. Haga, S. Shin, H. S. Suzuki, R. Arita andT. Kondo, Nat Commun 11, 2888/1-9 (2020).
electron-phonon coupling during photoinduced phase transition: T. Suzuki, Y. Shinohara, Y. Lu,
M. Watanabe, J. Xu, K. L. Ishikawa, H. Takagi, M. Nohara, N. Katayama, H. Sawa, M. Fujisawa, T. Kanai, J. Itatani,
T. Mizokawa, S. Shin and K. Okazaki, Phys. Rev. B 103, L121105 (2021).

Kimura group
Kimura group started in July 2020, and our group works on developing new microscopic imaging technologies using advanced
X-ray sources: X-ray free-electron lasers, synchrotron radiation, and high-order harmonics of ultrashort infrared laser pulses. In
2020, we developed a new X-ray microscopic imaging system at BL25SU of SPring-8 and BL1 of SACLA. We designed andfabricated novel X-ray optical components, such as focusing mirror and microfluidic device, by utilizing ultra-precision fabrication, measurement techniques, and semiconductor manufacturing processes.
1.

Chi-Feng Huang, Wei-Hau Chang, Ting-Kuo Lee, Yasumasa Joti, Yoshinori Nishino, Takashi Kimura, Akihiro Suzuki,
Yoshitaka Bessho, Tsung-Tse Lee, Mei-Chun Chen, Shun-Min Yang, Yeukuang Hwu, Shih-Hsin Huang, Po-Nan Li,
Peilin Chen, Yung-Chieh Tseng, Che Ma, Tsui-Ling Hsu, Chi-Huey Wong, Kensuke Tono, Tetsuya Ishikawa, and Keng
S. Liang: C.-F. Huang, W.-H. Chang, T.-K. Lee, Y. Joti, Y. Nishino, T. Kimura, A. Suzuki, Y. Bessho, T.-T. Lee, M.-C.
Chen, S.-M. Yang, Y. Hwu, S.-H. Huang, P.-N. Li, P. Chen, Y.-C. Tseng, C. Ma, T.-L. Hsu, C.-H. Wong, K. Tono,
T. Ishikawa and K. S. Liang, AIP Advances 10, 055219 (2020).

2.

Micro-liquid enclosure array and its semi-automated assembling system for x-ray free-electron laser diffractive imagingof samples in solution: T. Kimura, A. Suzuki, Y. Yang, Y. Niida, A. Nishioka, M. Takei, J. Wei, H. Mitomo, Y. Matsuo,
K. Niikura, K. Ijiro, K. Tono, M. Yabashi, T. Ishikawa, T. Oshima, Y. Bessho, Y. Joti and Y. Nishino, Review of Scientific Instruments 91, 083706 (2020).

3.

A highly efficient nanofocusing system for soft x rays: Y. Takeo, H. Motoyama, T. Shimamura, T. Kimura, T. Kume,
Y. Matsuzawa, T. Saito, Y. Imamura, H. Miyashita, K. Hiraguri, H. Hashizume, Y. Senba, H. Kishimoto, H. Ohashi and
H. Mimura, Applied Physics Letters 117, 151104 (2020).

4.

Design of two-stage soft-X-ray nano-focusing system with a ring-focusing mirror and quasi-Wolter mirror: Y. Takeo,
H. Motoyama, T. Shimamura, T. Kimura, T. Kume, Y. Matsuzawa, T. Saito, Y. Imamura, H. Miyashita, K. Hiraguri,
H. Hashizume, Y. Senba, H. Kishimoto, H. Ohashi and H. Mimura, in: PROCEEDINGS OF SPIE (SPIE, 2020),
114920N.

5.

Design of ultrashort Kirkpatrick-Baez mirror for soft x-ray nanofocusing: T. Shimamura, Y. Takeo, T. Kimura, H. Hashizume, Y. Senba, H. Kishimoto, H. Ohashi and H. Mimura, in: PROCEEDINGS OF SPIE (SPIE, 2020), 114920P.

* Joint research among groups within ISSP.

194

ISSP Activity Report 2020

The Institute for Solid State Physics (ISSP), The University of Tokyo
Address

5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8581, JapanPhone+81-4-7136-3207

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ISSP Activity Report 2020195