Progress of Facilities
Supercomputer Center
The Supercomputer Center (SCC) is a part of theMaterials Design and Characterization Laboratory (MDCL)of ISSP. Its mission is to serve the whole community ofcomputational condensed-matter physics of Japan, providing
it with high performance computing environment. In particular, the SCC selectively promotes and supports large-scalecomputations. For this purpose, the SCC invites proposals
for supercomputer-aided research projects and hosts theSteering Committee, as mentioned below, that evaluates the
proposals.
The ISSP supercomputer system consists of two subsystems: System B, which was replaced recently (Oct. 2020), isintended for larger total computational power and has morenodes with relatively loose connections whereas System C
is intended for higher communication speed among nodes.
System B (ohtaka) consists of 1680 CPU nodes of Dell
PowerEdge C6525 and 8 FAT nodes of Dell PowerEdge
R940 with total theoretical performance of 6.881 PFLOPS.
System C (enaga) consists of 252 nodes of HPE SGI 8600
with 0.77 PFLOPS. Replacement of the System C is scheduled in April 2022.
In addition to the hardware administration, the SCC
puts increasing effort on the software support. Since 2015,
the SCC has been conducting “Project for advancement ofsoftware usability in materials science (PASUMS)”. In thisproject, for enhancing the usability of the ISSP supercomputer system, we conduct several software-advancement
activities: developing new application software that runs
efficiently on the ISSP supercomputer system, adding new
functions to existing codes, help releasing private codesfor public use, creating/improving manuals for public
codes, etc. Three target programs were selected in fiscal
year 2020: (1) PHYSBO (proposal made by R. Tamura(NIMS)), (2) 2DMAT (proposal made by T. Hoshi (Tottori
Univ.)), and (3) MateriApps Installer (proposal made by
S. Todo (Univ. of Tokyo)). In 2021, we also started the datarepository service.
All staff members of university faculties or publicresearch institutes in Japan are invited to propose research
projects (called User Program). The proposals are evaluatedby the Steering Committee of SCC. Pre-reviewing is doneby the Supercomputer Project Advisory Committee. In fiscal
year 2020, totally 387 projects were approved including theones under the framework of Supercomputing Consortiumfor Computational Materials Science (SCCMS), which
specially supports FUGAKU and other major projects incomputational materials science. The total points applied andapproved are listed on Table. 1 below.
The research projects are roughly classified into thefollowing three (the number of projects approved, notincluding SCCMS):First-Principles Calculation of Materials Properties (189)Strongly Correlated Quantum Systems (40)
Cooperative Phenomena in Complex, Macroscopic
Systems (137)In all the three categories, most proposals involve bothmethodology and applications. The results of the projects arereported in 'Activity Report 2020' of the SCC. Every year 3-4
projects are selected for “invited papers” and published at
the beginning of the Activity Report. In the Activity Report
2020, the following three invited papers are included:1.
2.

“High precision study of the Anderson transition”,
Tomi OHTSUKI (Sophia U.) and Keith SLEVIN(Osaka U.)“Some Recent Developments in ab initio Thermodynamics of Ion Disorder in Solids”, Shusuke
KASAMATSU (Yamagata U.)

First semester (Apr.-Sep.)Class

Max Points

Application

System System
B
C

Numberof
Projects

Second semester (Oct.-Mar.)
Total Points

AppliedApproved

SystemB

SystemC

Class

SystemB

SystemC

Max Points

Application

System System
B
C

Numberof
Projects

Total Points
AppliedApproved

SystemB

SystemC

SystemB

System
C

A

100

50

any time

8

0.8k

0.4k

0.8k

0.4k

A

100

50

any time

10

1.0k

0.4k

1.0k

0.4k

B

500

100

twice a year

61

28.4k

4.0k

22.8k

3.9k

B

1k

100

twice a year

57

46.6k

3.2k

22.0k

2.0k

C

5k

1k

twice a year

115

446.5k80.1k239.8k

42.4k

C

8k

1k

twice a year

96595.8k

59.0k

226.0k

22.3k

D

10k

1k

any time

3

22.5k

2.0k

15.0k

2.0k

D

10k

1k

any time

0

0k

0k

0k

0k

E

15k

3k

twice a year9

127.4k

27.0k

88.5k

21.4k

E

25k

3k

twice a year7

175.0k

18.0k

87.0k

8.4k

S

–

–

twice a year

0

0

0

0

0

S

–

–

twice a year

0

0

0

0

0

SCCMS

11

23.7k

4.6k

23.7k

4.6k

SCCMS

10

50.0k

4.5k

50.0k

4.5k

Total

207

649.3k

118.0k

390.6k

74.6k

Total

180

868.3k

85.0k

386.0k

37.5k

Table 1. Research projects approved in 2020
The maximum points allotted to the project of each class are the sum of the points for the two systems. Computation of one node for 24 hours
corresponds to one point for the CPU nodes of System B and System C. The FAT nodes require four points for a 1-node 24-hours use.

56

ISSP Activity Report 2020

3.

“Large-Scale Molecular Dynamics Simulations ofKarman Vortex and Sound Wave: Cavitation andPolymer Effects”, Yuta ASANO (ISSP), Hiroshi
WATANABE(Keio Univ.) and Hiroshi NOGUCHI(ISSP)

Neutron Science Laboratory
The Neutron Science Laboratory (NSL) has been playing
a central role in neutron scattering activities in Japan since
1961 by performing its own research programs as well as
providing a strong General User Program (GUP) for theuniversity-owned various neutron scattering spectrometers
installed at the JRR-3 (20 MW) operated by Japan Atomic
Energy Agency (JAEA) in Tokai, Ibaraki (Fig. 1). In 2003,
the Neutron Scattering Laboratory was reorganized as the
Neutron Science Labora­tory to further promote the neutronscience with use of the instruments in JRR-3. Under GUP
supported by NSL, 12 university-group-owned spectrom­eters in the JRR-3 reactor are available for a wide scope of
researches on material science. The submitted proposals
were about 300 and the visiting users reached over 6000
person-day in FY2010. In 2009, NSL and Neutron Science
Division (KENS), High Energy Accelerator Research
Organization (KEK) built a chopper spectrometer, High
Resolution Chopper Spectrometer, HRC, at the beamline BL12 of MLF/J-PARC (Materials and Life Science
Experimental Facility, J-PARC) (Fig. 2). HRC covers wide
energy transfer (100 μeV < ħω < 0.5 eV) and momentum
transfer (0.03 Å-1 < Q < 30 Å-1) ranges, and therefore
becomes comple­mentary to the existing inelastic spectrometers at JRR-3. HRC has accepted general users through the
J-PARC proposal system since FY2011.
Triple axis spectrometers, HRC, a four-circle diffractometer, and a high resolu­
tion powder diffractometer are
utilized for a conventional solid state physics and a varietyof research fields on hard-condensed matter, while in thefield of soft-condensed matter science, researches aremostly carried out by using a small angle neutron scattering(SANS-U) and/or neutron spin echo (iNSE) instruments. The
upgraded time-of-flight (TOF) inelastic scattering spectrometer, AGNES, is available both for hard- and soft-matterscience. Our GUP has produced 2068 publications and 285
dissertations until April 30, 2021. Their lists for the last 10
years are given in Activity Report on Neutron Scattering
Research which is available in ISSP and NSL web pages.

Fig. 2. Schematic view of HRC.

Since the Great East Japan Earthquake on March 11,
2011, JRR-3 had been closed mainly from safety issues.
Hence, our domestic activity was only on HRC. To takeup a recent research highlight, well-defined spin wave was
successfully measured in the pressure-induced magneticphase in CsFeCl3 [1]. Collaboration between HRC and
CTAX, which is mentioned below, has clarified the hybridization of phase and amplitude modes near a quantum
critical point [2]. Another progress on HRC was that asuperconducting magnet up to 5 T became available. Field
dependence of spin-wave spectra in 2D antiferromagnet
Ba2MnGe2O7 was measured. From FY2012 to FY2020,
NSL has managed User-Program Supports for Overseas
Experiments. 398 people (for 297 proposals) have performed
their experiments in various foreign facilities and published
114 papers. The lists for this program are also available in
Activity Report on Neutron Scattering Research mentioned
above.
As for international cooperative programs, NSL operates
the U.S.-Japan Coopera­tive Program on neutron scattering,
providing further research opportunities to material scientists
who utilize the neutron scattering technique for their researchinterests. In 2010, relocation of the U.S.-Japan triple-axis
spectrom­eter, CTAX, was completed, and it is now open tousers. NSL has another agreement with Australian Centre for
Neutron Scattering (ANSTO), which was the main foreign
facility for the User-Program Supports for Overseas Experiments.
It is really good news that JRR-3 has restarted in
February 2021 after long shutdown and the normal GUP
will come back from July 2021. During the shutdown
period, we had been concentrating our efforts on upgrading
the instruments and neutron beam circumstances. Specificactions taken include: the installation of focusing collimation systems, such as focusing monochromator and focusing
analyzer, and material lens; and the introduction of polarization optics together with the installation of non-magnetization neutron shield. The neutron guides in the Guide Hall
have also been upgraded by replacing the existing ones
with super-mirror guides. These upgrades should result inincrease in neutron beam flux several times. The sample
environments such as cryostat and pressure cells have also
been upgraded. We are looking forward to restarting science
activities in JRR-3.
[1] S. Hayashida et al., Phys. Rev. B 97, 140405(R) (2018).
[2] S. Hayashida et al., Sci. Adv. 5, eaaw5639 (2019).

Fig. 1. Reactor hall of JRR-3. Three triple axis spectrometers are shownin the photo.

ISSP Activity Report 202057

International MegaGauss
Science Laboratory
The objective of this laboratory (Fig. 1) is to study thephysical properties of solid-state materials (such as metals,
semiconductors, insulators, superconductors, and magnetic
materials) in a high magnetic field of 100 T or even higher.
Such a high magnetic field can control material phases andfunctions. Our pulsed magnets, at moment, can generate up
to 87 Tesla (T) by non-destructive manner, and up to 1200
T by destructive manner. The world record indoor magnetic
field 1200 T was achieved in 2018. The laboratory is open
for scientists in domestic as well as from overseas. Lots offruitful results have come out not only from the collaborative
researches but also from our in-house activities.

Fig. 1. The building C of the IMGSL.

Building C
Room
101-113

Bmax

Type

ElectroMagnetic
Flux Compression

Destructive

Horizontal
Single-turn Coil

Destructive

300 T
200 T

10 mm
6μs
5 mm
10 mm

VerticalSingle-turn Coil

Destructive

300 T
200 T

8μs
5 mm
10 mm

1200 T

60 T
Building C
Room
114-120

Building C
Room 121

Pulse width
Bore

Alias

3μs

(100-1200T)

Power source

Applications

Others

5 MJ, 50 kV
2 MJ, 50 kV

Magneto-Optical
Magnetization

5 K – room
temperature

0.2 MJ, 50 kV

Magneto-Opticalmeasurements
Magnetization

5 K – room
temperature

0.2 MJ, 40 kV

Magneto-Optical
Magnetization

2 K – room
temperature

0.9 MJ, 10 kV

Magneto-Optical measurements
Magnetization
Magneto-Transport
Hall resistance
Polarization
Magneto-Striction
Magneto-Imaging
TorqueMagneto- Calorimetry
Heat Capacity

40 ms
18 mm

Mid-pulse Magnet Non-destructive
70 T

Our interests cover the study on quantum phase transitions (QPT) induced by high magnetic fields. Field-induced
QPT has been explored in various materials such as quantum
spin systems, strongly correlated electron systems and othermagnetic materials. One of our ultimate goals is to provide
the joint-research users with a 100 T millisecond-long pulse
using a non-destructive magnet, and to offer versatile highprecision physical measurements. Measurable physicalquantities or properties are magneto-optical spectra, magnetization, magnetostriction, electrical transport, specific heat,
nuclear magnetic resonance, and ultrasound propagation.
They can be carried out with sufficiently high accuracy.
Another ultimate goal is to extend the magnetic field region
and discover novel phenomena happening only in extremely
strong magnetic fields exceeding 100 T. Recent technicaldevelopments allow us to even measure magnetostriction
and ultrasound propagation in the destructive magnetic
fields over 100 T, that can directly reach potential structuralchanges in the ultrahigh magnetic fields. Recent discovery ofmagnetic field induced insulator-metal transitions of strongly
correlated materials in 500 T would open new direction of
the megagauss field research, namely exploration of fieldinduced novel phases in materials with strong interactions
comparable to thermal energy of a room temperature.
A 210 MJ flywheel generator (Fig. 2), which is the world
largest DC power supply (recorded in the Guinness Book ofWorld Records) was installed in the DC flywheel generator
station at our laboratory, and used as an energy source ofsuper-long pulse magnets. The magnet technologies areintensively devoted to the quasi-steady long pulse magnet

40 ms
10 mm

PPMS

Steady14 T

ResistanceHeat Capacity

MPMS

Steady7T

Magnetization

87 T(2-stage pulse)

5 ms
10 mm

Short-Pulse Magnet Non-destructive
Building K
Long-Pulse Magnet Non-destructive

85 T

5 ms
18 mm

43.5 T

1s
30 mm

ISSP Activity Report 2020

Lowest temperature
0.1 K

Down to 0.3 K

0.5 MJ, 20 kV

Magnetization
Magneto-Transport

2 K – room
temperature

210 MJ, 2.7 kVResistance
Magneto-Calorimetry

2 K – room
temperature

Table 1. Available Pulse Magnets, Specifications

58

Independent
Experiment in 5 site

Fig. 4. Schematic picture of the V-type single-turn coil equipped witha 40 kV, 200 kJ fast capacitor bank system. The liquid-helium-bathcryostat with a plastic tail is also shown.

Fig. 2. Upper: The K-building for the flywheel generator (left handside) and a long pulse magnet station (right hand side). Lower: The
flywheel giant DC generator which is 350 ton in weight and 5 m high(bottom). The generator, capable of a 51 MW output power with the
210 MJ energy storage, is planned to energize the long pulse magnet
generating 100 T without destruction.

(an order of 1-10 sec) energized by the giant DC power
supply. The giant DC power source will also be used for the
giant outer-magnet coil to realize a 100 T nondestructive
magnet by inserting a conventional pulse magnet coil in its
center bore. Recently, the super-long pulsed magnet has been
intensively used to investigate thermal properties such as
specific heat and magnetocaloric effects.
Magnetic fields exceeding 100 T can be obtained with
only destruction of a magnet coil. The ultrahigh magnetic
fields are obtained in a microsecond time scale. The project,financed by the ministry of education, culture, sports,science and technology aiming to generate 1000 T withthe electromagnetic flux compression (EMFC) system(Fig. 3), has been completed. Our experimental techniques
using the destructive magnetic fields have intensively beendeveloped. The system which is unique to ISSP in theworld scale is comprised of a power source of 5 MJ maincondenser bank and 2 MJ condenser bank. Two magnet
stations are constructed and both are energized from eachpower source. Both systems are fed with another 2 MJ
condenser bank used for a seed-field coil of which magnetic
flux is to be compressed. The 2 MJ EMFC system cangenerate 450 T. The 5 MJ system is used for generation ofFig. 3. A view of the coil setup of the electromagnetic flux compression
inside of an anti-explosive house. The world strongest indoor magnetic
field 1200 T was achieved in 2018.

1000 T-class magnetic field. For the research in magnetic
field range of 100 - 300 T, we have two single-turn coil
(STC) systems that have a fast-capacitor bank system of
200 kJ for each. One is the horizontal type (H-type) and theother is a vertical type (V-type, Fig. 4). Various kinds of laser
spectroscopy experiments such as the cyclotron resonanceand the Faraday rotation are possible using the H-type STC,
while a stable low temperature condition of 2 K is available
for the V-type STC.

Center of Computational
Materials Science
With the advancement of hardware and software technologies, large-scale numerical calculations have been making
important contributions to materials science and will haveeven greater impact on the field in the near future. CCMS
is a specialized research center established in 2011 forpromoting computer-aided materials science with massively
parallel computers, such as the Fugaku supercomputer,which has been recently developed in Kobe as the coreof a billion-dollar national project. Activities of CCMS
are divided into the following three categories: (1) highly
efficient and large-scale use of the Fugaku supercomputerand its application to grand-challenge problems in computational materials science, (2) activities as the center for thecommunity of computational condensed matter physics andmaterials science, and (3) computational physics researchaiming to solve rare-element problems.

Fig. 1. Group photo in the CDMSI symposium

ISSP Activity Report 202059

For the first category, each group in CCMS is carryingout various individual research projects in its own expertise to efficiently utilize large-scale parallel computers. For
example, the Ozaki group has been developing efficientand accurate methods and software packages to extend theapplicability of DFT to more realistic systems, and investigated the structural and electronic properties of various
2D materials in successful collaboration with experimentalgroups and industrial companies. There are other activities
such as development of Tensor Network (TN) based numerical methods and Markov-chain Monte Carlo methods by the
Kawashima group and the Todo group.
As for the activities in the second category, apartfrom major annual conferences and formal international
meetings as shown in Fig. 1, the CCMS/CDMSI hosted, andalso provided a series of lectures and training sessions at
Kashiwa. For example, training sessions "Kashiwa HandsOn" for getting accustomed to various application programs,
such as OpenMX, HΦ, mVMC, AkaiKKR, and MateriApps
LIVE!, as shown in Fig. 2, have been held monthly. Eachsession is designed for 5-10 trainees and takes 4-5 hours. We
also coordinate the use of the computational resources available to our community, and support community members
through various activities such as administrating the website"MateriApps" for information on application software incomputational science as shown in Fig. 3.
For the third category, the Akai team and the Fukushimagroup are working on the development of new permanent
magnet materials. In order to meet the ever-increasing
demands for new permanent magnet materials that are used
for high performance permanent magnets, CCMS is theoretically investigating the various magnetic properties, such as
saturation magnetization, Curie temperature, and magnetic

anisotropy, of iron-based magnetic materials, including rareearth magnet materials, R2(Fe,Co)14B, R2(Fe,Co)17, andRFe11.5Ti0.5 (R = La, Ce, … , Lu, Y) on the basis of firstprinciples calculations.
These activities are supported by funds for various
governmental projects including Element Strategy Initiative
and the Program for Promoting Researches on the Supercomputer Fugaku.
The following is the selected list of meetings organized
by CCMS in recent years:• 2019/10/8-2019/10/10 The 3rd Innovation Camp
for Computational Materials Science (3rd ICCMS),Takinoyu Hotel, Yamagata.
• 2019/12/6 TIA-Kakehashi Poster Workshop 2019 The
University of Tokyo Kashiwa Campus Station Satellite,
Kashiwa• 2019/12/13 Element Strategy Initiative Advisory
Council (ESIAC) 2019, TKP Garden city, Yokohama.
• 2020/2/3-2020/2/4 4th Element Strategy Symposium:
New Developments in Industry-Academia Research
Collaboration, Ito Hall, Tokyo.
• 2020/2/25 PCoMS Skill improvement training for
graduate students & postdocs ISSP, Kashiwa.
• 2020/6/19∙2020/6/23 Matching Workshop for industries& graduate students/ postdocs, Online.
• 2020/12/21-2020/12/22 Joint Research Meeting of ISSP
Supercomputer Joint Use and CCMS Annual Activity
Report 2020, Online.
In addition to the events listed above, we organize regularhands-on program for various application, such as Open MX
and HΦ.

Laser and Synchrotron Research Center(LASOR Center)Fig. 2. Software in the CCMS community

Fig. 3. MateriApps Website

60

ISSP Activity Report 2020

Laser and synchrotron research center (LASOR Center)
was established in October 2012 to push the frontiers of
the photon and materials science. LASOR has 10 groups
in 2019, which is the biggest division in ISSP. Most of theresearch activities on the development of new lasers with anextreme performance and the application to materials science
are studied in specially designed buildings D and E withlarge clean rooms and the isolated floor from the vibrationsin Kashiwa Campus. On the other hand, the experiments
utilizing the synchrotron radiation are performed at beamline
BL07LSU in SPring-8 (Hyogo).

Fig. 1. Optical frequency comb

Fig. 2. Close look of a high-peak-power ultrashort-pulse laser

Fig. 4. Phase-dependence of high harmonic spectra in soft X rays.

The development of novel laser-based light sources in thevacuum-ultraviolet to soft-X-ray regions innovated materials
investigations as represented by the highest-energyresolution photoemission, ultrafast time-domain, and ultrafast non-linear spectroscopies. Materials science research
powered by lasers thus has entered a new era. The ultra-shortand high-power lasers are more and more attractive lightsource for both basic science and industry. The state-of-theart laser source and spectroscopy are intensively explored.
Another stream pursued at ISSP is the synchrotron-based
research. The drastic advance in brilliance of the synchrotron
radiation has also opened a new field of its own in photon
science. The soft-X-ray beam-line in SPring-8 (BL07LSU)
was implemented with the longest undulator in the world:
The end stations illuminated by the brilliant soft-X-rays
are used to output innovative achievements based on highresolution spectroscopy data. In 2018, Japanese government
has made a statement to construct a new synchrotron facilityin Tohoku. LASOR has decided to subjectively contribute tothis facility from the design to the operation.
Lasers and synchrotrons have developed independently;
now both light sources cover a wide photon-energy range
with an overlap in the vacuum-ultraviolet to soft-X-ray
regions. Foreseeing their common interests in research fields
and technologies, ISSP integrated the two streams, namely
the extreme lasers and synchrotron radiations, into thecommon platform. Through the mutual interactions between
the forefronts of lasers and synchrotrons, LASOR will be
the center of innovations in light and materials science, withthe aid of world-wide joint research and close collaborations
with other divisions in ISSP such as New Materials Science,
Nanoscale Science, and Condensed Matter Theory.

Fig. 3. Design of E building for extreme VUV- and SX-lasers and newspectroscopy.

Fig. 5. 10-MHz high harmonic generation in an enhancement cavity.

The mission of LASOR is to cultivate and propel thefollowing three scientific fields:
1. Laser Science,
2. Synchrotron radiation Science,
3. Extreme Spectroscopy,• Laser science group
We were committed to continuing to developed various
state-of-the-art laser systems such as high-power solid-stateor gas lasers, high-intensity lasers, ultra-short pulse lasers
down to attosecond time scale (Peta Hz linewidth), ultrastable lasers with 1-Hz linewidth, optical frequency combs,
mid-infrared lasers, THz light source, and semiconductor
lasers.
High-power and ultrashort pulse laser technology has
progressed for this 10 years. It opened two directions ofresearch. One is a coherent extreme ultraviolet light source
realized by a high-harmonic generation (HHG) scheme. The
average power of HHG became high enough to use it for a
photoemission spectroscopy. The photon energies of 7 eV
to 60 eV are now available. They can be either very narrow
band width or ultrashort pulse. The other is an industrial
science such as a laser processing. Pulse duration variable,
100-W average power, femtosecond laser is now available in
LASOR for any collaborative research including companies.

ISSP Activity Report 202061

Fig. 6. Pump-probe photoemission system using 60-eV laser

We also aim to develop novel laser spectroscopy andcoherent non-linear optical physics, enabled via emerging
lasers and optical science/technology, and extensively study
basic light-matter physics, optical materials science, andapplied photonics. Such researches include ultrafast spectroscopy for excited state dynamics, terahertz magnetic-field
spectroscopy for spin dynamics, quantitative micro-spectroscopy on semiconductor lasers and nano-structure photonics
devices, such as quantum wire lasers, gain-switch semiconductor laser, multi-junction solar cells, and bio-luminescentsystems.
• Synchrotron radiation science group
By inheriting and developing the synchrotron techniques
cultivated for more than 20 years, we continuously develop
world cutting-edge spectroscopies such as time-resolved
photoemission/diffraction, ultrahigh resolution soft X-ray
emission, 3D (depth + 2D microscopy) nano ESCA and
X-ray magneto-optical effect and provide these techniques
both for basic material science and for applied science,
which contributes to the device applications in collaboration
with outside researchers. In order to pioneer new spectroscopies for the next-generation light sources, we upgrade
fast polarization switching of the undulator light source incooperation with SPring-8. In addition, we promote frontier
works on the use of X-ray free electron lasers, SACLA withhigh spatial and temporal coherence comparable to opticallasers in collaboration with scientists of laser light sources
and spectroscopies.

Fig. 7. Photonics devices under study: (left panel) semiconductor
quantum wires and (right panel) firefly-bioluminescence system
consisting of light emitter (oxyluciferin) and enzyme (luciferase)

62

ISSP Activity Report 2020

• Extreme spectroscopy group
The advent of laser-based light sources in the soft-X-ray
region is opening a new stage in the field that has been cultivated by the synchrotron radiations. One of the milestones
is to develop a laser-based light source of ~7 eV for the
sub-meV-resolution photoemission spectroscopy. In thisfive years, available photon energy became 11 eV with helpof Yb-fiber laser technology. It has high photon flux (1014photons/sec) with sub picosecond time resolution. Laserbased spin-resolved ARPES was realized in LASOR. This
technology would open brand-new spectroscopy. Highharmonic generation based photoemission spectroscopy
in the 20-60 eV region is another direction to be pursued.
Time-domain spectroscopy in the femtosecond region wasachieved. Combined with the picosecond time-domain
spectroscopy utilizing the pulsed light delivered fromsynchrotrons, we investigate the electronic structures anddynamics of matter in bulk, on surface, and into the nanoscale. The ultimate objective is to expand the soft-X-ray
operando methodologies by lasers. Diffractions, magnetooptical effects, and inelastic scatterings now done at synchrotrons will be performed by lasers, to access the real-time
dynamics of chemical reactions and phase transitions down
to the femtoseconds.
State-of-the-art laser based organism spectroscopy is a
new direction in LASOR. ISSP research area is shifting from
simple material and science to complex one including living
body and functional material with excited state physics.

Synchrotron Radiation Laboratory
The Synchrotron Radiation Laboratory (SRL) was established in 1975 as a research division dedicated to solid statephysics using synchrotron radiation (SR). Currently, SRL is
composed of two research sites, the Harima branch and theE-building of the Institute for Solid State Physics.
• Brilliant soft X-ray beamline at Harima branch
In 2006, the SRL staffs have joined the Materials
Research Division of the Synchrotron Radiation Research
Organization (SRRO) of the University of Tokyo and they
have played an essential role in constructing a new highbrilliant soft X-ray beamline, BL07LSU, in SPring-8. The

Fig. 1. Ambient pressure photoemission

Fig. 2. 3D nano-ESCA stationcontrolled 25-m long soft X-ray undulator. In 2020, 24 usergroups made their experiments during the SPring-8 operation
time. The number is slightly decreased compared with theusual annual operation because of the COVID-19 problem.
The official beamtime was cut off in April and May andreplaced by the beamtime in the latter half of 2020.
• High-resolution Laser SARPES at E-building

Fig. 3. Soft X-ray emission station

light source is the polarization-controlled 25-m long soft
X-ray undulator with electromagnetic phase shifters thatallow fast switching of the circularly (left, right) and linearly(vertical, horizontal) polarized photons.
The monochromator is equipped with a varied linespacing plain grating, which covers the photon energy range
from 250 eV to 2 keV. At the downstream of the beamline, a
lot of experimental stations have been developed for frontier
spectroscopy researches: three endstations, i.e. ambientpressure photoemission (Fig. 1), three-dimensional (3D)
nano-ESCA (Fig. 2), high resolution soft X-ray emission
spectroscopy (XES) (Fig. 3) stations are regularly maintainedby the SRL staffs and open for public use, and at free-port
station many novel spectroscopic tools have been developedand installed such as soft X-ray resonant magneto-optical
Kerr effect (XMOKE) and so on. The beamline construction was completed in 2009 and SRL established the Harimabranch laboratory in SPring-8. At SPring-8 BL07LSU, each
end-station has achieved high performance:the time-resolved
soft X-ray spectroscopy (TR-SX) station equipped with a
two-dimensional angle-resolved time-of-flight (ARTOF)
analyzer has established the laser-pump and SR-probe
method with the time-resolution of 50 ps which corresponds to the SR pulse-width. This apparatus was moved
to E-building in the 2020 summer to realize better temporal
resolution using the fsec high harmonic laser pulse of
11 eV; the 3D nano-ESCA station reaches the spatial resolution of 70 nm; the XES station provides spectra with theenergy resolution around 70 meV at 400 eV and enables
real ambient pressure experiments. Soft X-ray resonant
MOKE station has been developed to make novel magnetooptical experiment using fast-switching of the polarization-

High-resolution Laser Spin- and Angle-Resolved Photoemission Spectroscopy (SARPES) is a powerful technique
to investigate the spin-dependent electronic states in solids.
In FY2014, LASOR and SRL staffs constructed a new
SARPES apparatus (Fig. 4), which was designed to provide
high-energy and -angular resolutions and high efficiency ofspin detection using a laser light at E-building. The achievedenergy resolution of 1.7 meV in SARPES spectra is thehighest in the world at present. From FY2015, the new
SARPES system has been opened to outside users.
The Laser-SARPES system consists of an analysis
chamber, a carousel chamber connected to a load-lockchamber, and a molecular beam epitaxy chamber, which
are kept ultra-high vacuum (UHV) environment and areconnected to UHV gate valves. The electrons are excitedwith 6.994-eV photons, yielded by 6th harmonic of a
Nd:YVO4 quasi-continuous wave laser with a repetition
rate of 120 MHz, and 10.7 eV photons, driven by the third
harmonic radiation at 347 nm of an Yb:fiber chirped pulse
amplifier laser, which was developed by Kobayashi's lab in
LASOR. The hemispherical electron analyzer is a custommade Scienta Omicron DA30-L, modified for installing thespin detectors. The spectrometer is equipped with two highefficient spin detectors associating very low energy electron
diffraction are orthogonally placed each other, which allows
us to analyze the three-dimensional spin polarization ofelectrons. At the exit of the hemispherical analyzer, a multichannel plate and a CCD camera are also installed, whichenables us to perform the angle-resolved photoelectron
spectroscopy with two-dimensional (energy-momentum)
detection. The laser-SARPES with 7-eV laser can provide
both high-resolution spin-integrated and spin-resolved photoemission spectra in various types of solids, such as spin-orbit
coupled materials and ferromagnetic materials. In addition,using the 10.7-eV makes it possible to follow their ultrafast
spin dynamics in the time domain by pump-probe scheme.

Fig. 4. Laser-SARPES system at E-building

ISSP Activity Report 202063