Tohru Suemoto
Emeritus Professor, University of Tokyo[Present Position]
Fellow at Toyota Physical and Chemical Research Institute[Research Field]
Materials Photoscience, Ultrafast Spectroscopy[Date of Birth]
September 21, 1950

[Sex] Male[Nationality] Japan[Graduation and Degree]
Mar. 1973 Faculty of Science (physics). Kyoto University
Mar. 1975 Graduate School of Science, Master Course, University of Tokyo
Mar. 1978 Graduate School of Science, Doctor Course (physics major), University of Tokyo
Mar. 1978 Doctor of Science, University of Tokyo(Thesis title: Spectroscopic Studies on the Excited Electronic Statesin Condensed Rare Gases)[Professional Career]Mar. 1980 - Jan. 1984

Research Associate, Research Institute for Scientific
Measurements, Tohoku University.
Jan. 1984 - Mar. 1989
Associate Professor, Research Institute for Scientific
Measurements, Tohoku University.
[Feb. 1985 - Nov. 1986; Visiting Scientist at Max Planck Institute for Solid State Research,
partly as a Humboldt Fellow (Germany)]
Apr. 1989 - Feb. 2001
Associate Professor, Institute for Solid State Physics,
University of Tokyo.
Mar. 2001 – Mar. 2016
Professor, Institute for Solid State Physics, University ofTokyo.
Apr. 2016 – Present
Fellow at Toyota Physical and Chemical Research Institute[Apr. 2016 - Present; Visiting Professor at Osaka University (Institute of Laser
Engineering)][Membership]
Physical Society of Japan, The Japan Society of Applied Physics, The SpectroscopicalSociety of Japan, Optical Society of America.

Summary of my research work
Tohru Suemoto
1. Overview
Since my graduate course at the University of Tokyo, I have been working in the field ofspectroscopy on the solid state materials. The wavelength (frequency) of the spectroscopy I comitted
has not been restricted within optical region, but ranged from terahertz to soft X-ray. I concerned withvariety of materials including semiconductors, oxides, metal complexes, magnets, metals, semimetals
and biomolecules, through collaborations with material scientists and chemist.
In the following the main subjects I have been engaged in so far are summarized.
1) Self-trapped excitons in solid rare gases (doctor work at the University of Tokyo)
2) Quasi-elastic light scattering in superionic conductors (Tohoku University)3) Resonant Raman scattering in semiconductor quantum well structures(Max Planck Institute for Solid State Research)
4) Persistent hole-burning in rare earth ion doped solids5) Carrier dynamics in semiconductors studied with time-resolved electronic Raman scattering.
6) Resonant excitation spectroscopy of semiconductor nanostructures i.e., porous silicon.
7) Nuclear wave-packet dynamics and carrier dynamics studied with femtosecond luminescence
spectroscopy.
8) Dynamics of photoinduced phase transitions.
9) Dynamics of spin systems studied with terahertz spectroscopy.
10) Observation of laser ablation processes by time resolved soft X-ray interferometer.
I will describe the outline of the topics, which have continued until 2016 (items 7-10) in the following
sections.
2. Femtosecond luminescence spectroscopy
Luminescence phenomenon has long been known to provide versatile tools for investigating theexcited electronic states with high sensitivity and straight forward interpretation. For time-resolved
observation of luminescence, high speed photodiodes, streak cameras, optical Kerr shutters, etc. arewidely used. Among them, the up-conversion method has the highest time resolution in measurementof luminescence. This situation has not changed since the 1990s up to the present time[1].
2.1 Dynamics of wave-packet
In the up-conversion method, as shown in Fig. 1 (a), light emitted from a sample and the gating
pulse from a laser are mixed in a nonlinear optical crystal to generate sum frequency (up-conversion)light, and this is directed to a spectrometer and detected by a photomultiplier or semiconductor devices.
As the sum frequency is generated only when the luminescence light and the gating light are present in
the crystal at the same time, the luminescence can be cut out in time by adjusting the relative time delay
between the pumping and gating pulses. We used this method to observe the nuclear wave-packet
dynamics in the localized excited states. During the wave-packet motion on the adiabatic potential
1surface as shown in Fig. 1 (b), the luminescence photon energy changes depending on the position of
the wave-packet on the potential surface [2]. By using this fact, not only the position of the wave packet,
but also its shape can be captured.
Figure 1 (c) shows the temporal evolution of the luminescence spectrum observed for the selftrapped excitons generated by a pumping pulse in bromine-bridged platinum complex [3]. It can be seenthat the peak position of the spectrum oscillates with time. Furthermore, the spectrum cut out at eachtime point reflects the shape of the wave-packet. Therefore, we refer to the frames arranged inchronological order as "wave packet movies". In the subsequent research, it was possible to visualize
the splitting of the wave-packet into oscillating part and the traveling part, the latter corresponding to
the transition of the lattice arrangement to a new state overcoming a potential barrier. In the same
experiment, the nodes and antinodes of the wave function constituting the wave packet are resolved.

Fig. 1 (a) Principle of time-resolved luminescence measurement by up-conversion method. (b)Generation of wave-packet on the adiabatic potential surface by photoexcitation and the luminescenceprocess. (c) Time evolution of emission spectrum from self-trapped exciton in Br-bridged Pt complex.

2.2 Topological insulator
The topological insulator is a substance that basically is an insulator inside, but has a metallic band
structure with continuous density of states on the surface. The topologically protected surface state is
the two dimensional Dirac electron system with low carrier scattering rate and attracting attention fromengineering view point as a platform for high speed electronic devices. The carrier dynamics in thissystem is now extensively studied by means of time-resolved photoemission spectroscopy. However,the luminescence approach has not been reported. Recently, we succeeded in observing the short lived
hot luminescence in the infrared region below band gap of the bulk by using up-conversion timeresolved luminescence spectroscopy [5]. Figure 2(b) shows the band structure of the topologicalinsulator TlBiSe2, which we studied in this work. The insulating bulk band structure having a band gapof 0.35 eV is shown by blue hatching and the surface Dirac cone is shown by crossing straight lines.
The important character of this system is the spin orientation locked to the momentum, that is, the spinorientation on the red line and blue line are opposite. Figure 2(a) shows the time-development ofluminescence, where the rise time and the decay time are very different below and above the band gap
20.35 eV. Fig. 2(c) summarizes this behavior. The luminescence below band gap cannot be assigned tobulk and should be ascribed to the surface state. Unlike photoemission spectroscopy, luminescence
experiment can be performed even in the atmosphere, so it is expected to provide a useful tool forstudying the dynamic characteristics of the device in operation. We also studied the ultrafast relaxationof Dirac electrons in graphite [6] and graphene [7] by the same method.

Fig. 2 (a) Time evolution of luminescence in the topological insulator TlBiSe2 under excitation at a
photon energy of 1.55 eV. The photon energy of luminescence is shown on the left end of each curve.
(b) Band structure of TlBiSe2. (c) Photon energy dependence of rise time and decay time forluminescence.

3. Dynamics of photoinduced phase transition
The arrangement of atoms, polarization, magnetization, conductivity, etc. in materials can bechanged by applying pressure, magnetic field or changing temperature or other environment parameters.
These are known as phase transitions. In some cases, the phase transitions can be induced by lightirradiation and are called as "photoinduced phase transitions" (PIPT). Here, we discuss the PIPT in acyano-bridged metal complex (Prussian blue analog) RbxMn [Fe (CN) 6] y nH 2O [9]. As shown in Fig.
3 (a), the valence state of the metal ion at room temperature is Fe3+ - Mn2+ (HT - phase), but as thetemperature is lowered, a charge transfer transition occurs resulting in Fe2+- Mn3+ configuration (LT phase), and at the same time, the magnetic susceptibility. Since the frequency of the stretching mode of
the CN molecule bridging Fe and Mn reflects the valence of the adjacent metal ions, this vibrational
spectroscopy can be used to determine the valence of Fe and Mn [10]. Since the pairs Fe2+ - Mn2+ orFe3+ - Mn3+ appear at the boundary between the two phases as shown in the figure, it is possible toquantify the amount of boundary from vibration spectra. Figure 3 (b) shows the time evolution of theamounts of the high-temperature (HT) phase, the low-temperature (LT) phase and the boundary during
light irradiation obtained from the Raman scattering intensity. Here, we can see a conversion of the HT3phase into LT phase along with a marked increase of the boundary component. The amount of theobserved boundary component is far larger than that observed during HT to LT conversion by coolingthe sample. This indicates that the LT phase domain size in PIPT is very small [11]. Transient generationof a large amount of boundary component is also verified by time-resolved infrared absorption
measurements [12]. This was a rare example showing the dynamics of the nanometer scale domains
associated with PIPT.
(a)

(b)
Sum

HT phase

LT phase
Fe2+ - Mn3+

Fe3+

3+

2+ 2+

2+

3+

3+

2+

3+

2+

2+

3+

3+

HT phase

0.8

Mn2+

Fraction

Fe2+  Mn3+CN

1.0

Fe3+ - Mn2+
LT phase

0.6

Boundary(Fe3+-Mn3+)x2

0.4

0.2

0.0

20

40

15 %

60

80

100

Time (min.)Fig. 3 (a) Structure of RbxMn [Fe(CN)6]y nH2O. (b) Time evolution of high temperature phase, lowtemperature phase and boundary components during light irradiation.

4. Terahertz magnetic resonance
4.1 Coherent control of spin precession
Most of the research activities utilizing terahertz (THz) spectroscopy have been devoted to thephenomena induced via electric dipole moment transitions.

Fig. 4 (a) Excitation of a spin by pulsed magnetic field. (b) Circularly polarized FID radiation observedin -iron oxide. (c) Selective excitation of F and AF modes in YFeO3.
4

This is because the magnetic dipole transition is very weak in general (106 times lower than that ofelectric dipole transition in atomic systems). However, the magnetic dipole transition has an essential
importance in the magnetic resonance phenomena. As the frequencies of ferromagnetic and antiferromagnetic resonances are quite high and falls in sub-THz and THz region, the possibility of themagnetic resonance experiment utilizing THz radiation has become recognized since around 2010.
During experiments evaluating the THz transmission properties of a ferromagnetic material (-ironoxide), we found a free induction decay (FID) signal with circular polarization from a magnetizedsample under excitation by linearly polarized THz radiation [13].

Figure 4(a) illustrates themagnetization vector in a ferromagnetic material. The magnetic moment M initially parallel to z-axis istilted to y-axis direction by applying an impulsive magnetic field HTHz in x direction. Then M starts tomake a precession motion around z-axis. The screw-like trajectory in Fig. 4(b) shows the FID radiation
with circular polarization emitted from a magnetized -iron oxide in time domain. As the turning
direction was inverted when we inverted the magnetization, this was ascribed to the precession motionof the magnetization. Figure 4(d) shows a coherent control of spin precession in orthoferrite, which has
two magnetic modes at 0.3 THz(F-mode) and 0.53 THz (AF-mode) [14]. When the sample is excite bya single pulse, both modes are excited as shown by a black curve in Fig. 4(d). However, when we use apair of pulses with a time separation in-phase or out-of-phase of each mode as shown in Fig. 4(c), we
can selectively excite AF-mode or F-mode as shown by red or blue curve.
4.2 Coupling of spin excitation and metamaterial structure
A metal C-shaped split ring resonator (SRR) of several tens of micrometers (Fig. 5 (a)) has aresonance in sub-THz region.

Fig. 5 (a) Illustration of the sample with a split ring resonator. (b)(c) Waveforms and Fourier spectraof Faraday rotation signal. Upper panels and lower panels are experiment and calculation results,
respectively.

When we induce an electric current in the ring, using the electric field component of the THz wave, themagnetic flux passing through the ring is enhanced by nearly one order of magnitude than that containedin the same THz wave. This strong magnetic field can be used to drive the spins in the substrate. The
5

precession motion monitored by Faraday rotation is shown in the upper part of Fig. 5 (b). The resonancefrequency of the spin can be tuned by varying the temperature and the amplitude significantly increases
when it matches the resonance frequency of the ring. Figure 5 (c) shows the Fourier spectra of theoscillation. The lower parts of (b) and (c) are the calculation results based on the model assuming acoupling between the spin system and the LC resonance circuit, showing very good agreement with theexperimental results [15].
4.3 Production of macroscopic magnetization by THz wave
ErFeO3 undergoes a spin reorientation phase transition between 87 and 96 K, that is, themagnetization direction is parallel to the a-axis at low temperature, it starts to rotate above 87 K towardc direction, and finally it aligns parallel to the c-axis at 96 K. Usually, in the case of temperature induced
reorientation, the domains with +c and -c orientation occur with equal probability and the macroscopic
magnetization becomes nearly zero. However, if we excite the precession motion of the spins by THz
magnetic field and input a heating pulse at an appropriate timing, we can make totally +c or -c polarized
macroscopic volume selectively [16]. The result is shown in Fig. 6. The dotted curve is the fluctuating
weak magnetization induced by the THz pulse irradiation at t=0. If the heating pulse (800nm) hits the
sample at 57 ps when the fluctuation is upward, the magnetization is amplified to about 100 times (redcurve) in positive direction. Similarly, the final magnetization is in negative direction (blue curve), if
the heating pulse comes at 65 ps. At the final stage (180ps), 80% of the spins are aligned in the same
direction in both cases. This demonstrates the possibility of ultrafast manipulation of macroscopic
magnetization, by using THz and optical pulses combined.

Fig. 6 Magnetic fluctuation induced by THz wave (dotted curve) and generation ofmacroscopic magnetization (red and blue curves) by THz pulse and heating pulse combined.

5. Single shot soft X-ray imaging
In most of the research on ultrafast phenomena using pump and probe technique, repeatablephenomena are targeted, because it is required to repeat the same phenomena for collecting informationin time sequence. Although this method is applicable to the phenomena such as electron dynamics, inwhich the system is believed to recover precisely the initial state after some waiting time. However,photoinduced phase transition, chemical reaction and destructive phenomena such as laser ablation are
6inherently irreversible and for investigating these phenomena requires a single-shot measurement
technique. In order to perform such measurement, a single shot soft X-ray interferometer wasconstructed using a soft X-ray laser (wavelength; 13.9 nm, pulse width; 7 ps) equipped at QTS Kansai
Laboratory as a light source. Figure 7(a) illustrates the outline of the system. The soft X-ray beams
reflected at the ablated area and the reference area on the same sample are merged at a very small angle
by using a double Loyd's mirror and incident on the X-ray CCD camera placed at a large distance. Fromthe shift of the interference fringes on the CCD camera, we can measure the dilation of the sample
surface with a picosecond time resolution [17].
Figure 7 (b) shows an interference image after irradiating the Au film with a Gaussian beam ofnear-infrared (800 nm, 70 fs) laser pulse to cause ablation. One fringe corresponds to 20 nm, anddisplacement can be read with an accuracy of about 1 nm. Although the expansion of the order ofmicrometer using visible light has been reported, observation at the initial stage of expansion with ananometer scale was made possible by the use of soft X-ray for the first time. Figure 7 (c) shows thereflectance image during ablation. Since the ablation is caused by the Gaussian beam, the excitation
density varies depending on the distance from the center. Existence of clear ring-shaped boundary lines
indicates that the ablation scheme changes discontinuously at certain excitation density.

Fig. 7 (a) is a conceptual diagram of a time-resolved soft X-ray interferometer. (b) Time resolved
interference image associated with laser ablation. (c) Soft X-ray reflection image during laser ablation.

References[1] Dynamics of nuclear wave packets at the F center in alkali halides (review), T. Koyama and T.
Suemoto, Rep. Prog. Phys. 74, 076502 (2011).
[2] quasi-one-dimensional halogen-bridged Pt complex, S. Tomimoto, S. Saito, T. Suemoto, K. Sakata, J.
Takeda, and S. Kurita, Phys. Rev. B 60, 7961-7965 (1999).
[3] Real-time capturing of the nuclear wave-packet shape in self-trapped excitons, T. Matsuoka, J. Takeda,
S. Kurita, and T. Suemoto, Phys. Rev. Lett. 91, 247402 (2003).
[4] Splitting dynamics of nuclear wave packets in a Peierls insulator using femtosecond laser spectroscopy,
Y. Takahashi, K. Yasukawa, S. Kurita, and T. Suemoto, Phys. Rev. B 81, 081102(R) (2010).
7

[5] Optically detecting the edge-state of a three-dimensional topological insulator under ambient conditions
by ultrafast infrared photoluminescence spectroscopy, S. Maezawa, H. Watanabe, M. Takeda, K.
Kuroda, T. Someya, I. Matsuda, and T. Suemoto, Sci. Rep. 5, 16443 (2015).
[6] Access to hole dynamics in graphite by femtosecond luminescence and photoemission spectroscopy, T.
Suemoto, S. Sakaki, M. Nakajima, Y. Ishida, and S. Shin, Phys. Rev. B 87, 224302 (2013).
[7] Layer number dependence of carrier lifetime in graphenes observed using time-resolved mid-infrared
luminescence, H. Watanabe, T. Kawasaki, T. Iimori, F. Komori, and T. Suemoto, Chem. Phys. Lett.
637, 58-62 (2015).
[8] Photoinduced metallic state in VO2 proved by the terahertz pump-probe spectroscopy, M. Nakajima, N.
Takubo, Z. Hiroi, Y. Ueda, and T. Suemoto, Appl. Phys. Lett. 92, 011907 (2008).
[9] Dynamics of photoinduced phase transitions in a Prussian blue analog studied by CN vibrational
spectroscopy (review), T. Suemoto, R. Fukaya, A. Asahara, H. Watanabe, H. Tokoro, and S. Ohkoshi,
Current Inorganic Chemistry, 6, 10-25 (2016).
[10] Photoinduced charge-transfer process in rubidium manganese hexacyanoferrate probed by Raman
spectroscopy, R. Fukaya, M. Nakajima, H. Tokoro, S. Ohkoshi, and T. Suemoto, J. Chem. Phys. 131,
154505 (2009).
[11] Growth Dynamics of Photoinduced Phase Domain in Cyano-Complex Studied by Boundary Sensitive
Raman Spectroscopy, A. Asahara, M. Nakajima, R. Fukaya, H. Tokoro, S. Ohkoshi, and T. Suemoto,Acta Physica Polonica A 121, 375-378 (2012).
[12] Ultrafast dynamics of reversible photoinduced phase transitions in rubidium manganesehexacyanoferrate investigated by midinfrared CN vibration spectroscopy, A Asahara, M Nakajima, R
Fukaya, H Tokoro, S. Ohkoshi, and T. Suemoto, Phys. Rev. B 86, 195138 (2012).
[13] Ultrafast time domain demonstration of bulk magnetization precession at zero magnetic field
ferromagnetic resonance induced by terahertz magnetic field, M. Nakajima, A. Namai, S. Ohkoshi,
and T. Suemoto, Opt. Exp. 18, 18260-18268 (2010).
[14] Coherent Control of Spin Precession Motion with Impulsive Magnetic Fields of Half-Cycle Terahertz
Radiation, K. Yamaguchi, M. Nakajima, and T. Suemoto, Phys. Rev. Lett. 105, 237201(2010).
[15] Enhanced spin-precession dynamics in a spin-metamaterial coupled resonator observed in terahertz
time-domain measurements, T. Kurihara, K. Nakamura, K. Yamaguchi, Y. Sekine, Y. Saito, M.
Nakajima, K. Oto, H. Watanabe, and T. Suemoto, Phys. Rev. B 90, 144408 (2014).
[16] Macroscopic Magnetization Control by Symmetry Breaking of Photoinduced Spin Reorientation with
Intense Terahertz Magnetic Near Field, T. Kurihara, H. Watanabe, M. Nakajima, S. Karube, K. Oto,
Y. Otani and T. Suemoto, Phys. Rev. Lett. 120, 107202-1-6 (2018)[17] Single-shot picosecond interferometry with one-nanometer resolution for dynamical surface
morphology using a soft X-ray laser, T. Suemoto, K. Terakawa, Y. Ochi, T. Tomita, M. Yamamoto, N.
Hasegawa, M. Deki, Y. Minami, and T. Kawachi, Opt. Exp. 18, 14114-14122 (2010).

8

Publication list（2018）
Tohru Suemoto
1.

Observation of relaxed exciton states in condensed argon
T. Suemoto, Y. Kondo, and H. Kanzaki
Phys. Lett. 61A, 131-132 (1977).

2.

Absorption spectra of self-trapped exciton in condensed rare gases
T. Suemoto, Y. Kondo, and H. Kanzaki
Solid State Commun. 25, 669-672 (1978).

3.

Time-resolved absorption spectroscopy of self-trapped excitons in condensed Ne, Ar, and Kr
T. Suemoto and H. Kanzaki
J. Phys. Soc. Jpn. 46, 1554-1562 (1979).

4.

Formation process of self-trapped exciton bubbles in solid neon
T. Suemoto and H. Kanzaki
J. Phys. Soc. Jpn. 49, 1039-1045 (1980).

5.

Relaxation processes from high excited states of self-trapped excitons in condensed neon
T. Suemoto and H. Kanzaki
J. Phys. Soc. Jpn. 50, 3664-3668 (1981).

6.

Determination of the ionic diffusion constant by using a quasi-elastic light scattering
T. Suemoto and M. Ishigame
Solid State Ionics 9&10, 1365-1367 (1983).

7.

Nature of relaxed excitons in rare gas solids
H. Kanzaki and T. Suemoto
Semicond. & Insul. 5, 345-359 (1983).

8.

Correlation between the quasi-elastic light scattering and the ionic-conductivity in superionic
conductors
T. Suemoto and M. Ishigame
Solid State Commun. 45, 641-644 (1983).

9.

Quasielastic light scattering in superionic β-alumina
T. Suemoto and M. Ishigame
Phys. Rev. B 32, 4126-4133 (1985).

10. Quasielastic light scattering in oxygen-ion conductors
T. Suemoto and M. Ishigame
Phys. Rev. B 33, 2757-2764 (1986).
11. Resonant Raman scattering in p-type GaAs-Al x Ga 1−x As-AlAs quantum wells
T. Suemoto, G. Fasol, and K. Ploog
Phys. Rev. B 34, 6034-6037 (1986).
12. Composition dependence of the ionic diffusion coefficients in yttria-stabilized zirconias
T. Suemoto and M. Ishigame
Solid State Ionics 21, 225-229 (1986).
13. Raman scattering studies of mobile ions in superionic conductor hollandites
Y. Shibata, T. Suemoto, and M. Ishigame
Phys. Stat. Solidi (b) 134, 71-79 (1986).
14. Electronic and vibronic structure of the (GaAs) 1 (AlAs) 1 superlatticeM. Cardona, T. Suemoto, N. E. Christensen, T. Isu, and K. Ploog
Phys. Rev. B 36, 5906-5913 (1987).
15. Determination of binding energies and wave functions in quantum wells from Raman resonance crosssection measurements
T. Suemoto, G. Fasol, and K. Ploog
J. Phys. Colloq. 48, C5-507-510 (1987).
16. Conduction-band nonparabolicity in p-type quantum wells and Fourier determination of the hole wave
functions by resonant Raman scattering
T. Suemoto, G. Fasol, and K. Ploog
Phys. Rev. B 37, 6397-405 (1988).
17. Quasielastic light scattering in one-dimensional superionic conductor hollandites
S. Furusawa, T. Suemoto, and M. Ishigame
Phys. Rev. B 38, 12600-12606 (1988).
18. Quasielastic light scattering in Tl-β"-gallate
T. Suemoto, Y. Takeda, and M. Ishigame
Solid State Commun. 68, 581-585 (1988).
19. Determination of ionic diffusion coefficients and activation energies in (ZrO 2 ) 1−x (YbO 1.5 ) x system byusing quasielastic light scattering
A. Nakajima, T. Suemoto, and M. Ishigame
Solid State Ionics 28-30, 512-517 (1988).
20. Raman scattering of the superionic conducting glasses in the systems AgI-Ag 2 O-MoO 3
S. Muto, T. Suemoto, and M. Ishigame
Solid State Ionics 35, 307-310 (1989).
21. Control of Oxygen Deficiency in Superconducting Y 1 Ba 2 Cu 3 O 7−y Films Using a Solid-StateElectrolyte
H. Yugami, T. Watanabe, T. Suemoto, S. Shin, S. Sobajima, and M. Ishigame
Jpn. J. Appl. Phys. 28, L1411-1414 (1989).
22. Quasielastic light scattering in superionic conductors
T. Suemoto
Solid State Ionics 40/41, 250-254 (1990).
23. Site-Selective Spectroscopy of Eu3+ in YSZ and Y3+-Doped CeO 2
H. Yugami, A. Koike, A. Nakajima, M. Ishigame, and T. Suemoto
Solid State Ionics 40/41 316-319 (1990).
24. Brillouin scattering in one-dimensional superionic conductor hollandites
S. Furusawa, T. Suemoto, and M. Ishigame
Solid State Ionics 42, 93-99 (1990).
25. Practical measurement of diffusion constants in sintered zirconias by using a light-scattering method
T. Suemoto and H. Arashi
J. Appl. Phys. 69, 3016-3021 (1991).
26. Local structures in the superionic conductor Y3+-doped CeO 2 studied using site-selective spectroscopy
H. Yugami, A. Nakajima, M. Ishigame, and T. Suemoto
Phys. Rev. B 44, 4862-4871 (1991).
27. Light scattering in superionic conductors (review)
M. Ishigame, S. Shin, and T. Suemoto

Solid State Ionics 47, 1-34 (1991).
28. Relationship between local structures and ionic conductivity in ZrO 2 -Y 2 O 3 studied by site-selective
spectroscopy
H. Yugami, A. Koike, M. Ishigame, and T. Suemoto
Phys. Rev. B 44, 9214-9222 (1991).
29. Fluorescence line narrowing study of Eu3+ in YSZ: A new direction of research in superionic materials
H. Yugami, T. Suemoto, and M. Ishigame
Solid State Ionics 48, 321-324 (1991).
30. Persistent spectral hole-burning of Pr3+ ions in yttria stabilized zirconia: a new hole-burning material
K. Tanaka, T. Okuno, H, Yugami, M. Ishigame, and T. Suemoto
Optics Commun. 86, 45-50 (1991).
31. Spin-wave-assisted photoluminescence in MnO at low temperatures
S. Mochizuki, B. Piriou, J. Dexpert-Ghys, N. Takayama, G. Kido, I. Mogi, and T. Suemoto
J. Phys.: Condens. Matter 4, 6501-6508 (1992).
32. Observation of phonon structures in porous Si luminescence
T. Suemoto, K. Tanaka, A. Nakajima, and T. Itakura
Phys. Rev. Lett. 70, 3659-3662 (1993).
33. Determination of intervalley scattering time in germanium by subpicosecond time-resolved Raman
spectroscopy
K. Tanaka, H. Ohtake, and T. Suemoto
Phys. Rev. Lett. 71, 1935-1938 (1993).
34. Homogeneous line width of praseodymium ions in various inorganic materials
T. Okuno, K. Tanaka, K. Koyama, M. Namiki, and T. Suemoto
J. Lumin. 58, 184-187 (1994).
35. Luminescence side bands due to distributed Stark levels in Pr3+:ZrO 2 -Y 2 O 3 (YSZ)
T. Okuno, K. Tanaka, K. Koyama, and T. Suemoto
J. Lumin. 60&61, 85-88 (1994).
36. c-Si like phonon structures in the luminescence of porous Si
T. Suemoto, K. Tanaka, A. Nakajima, and T. Itakura
J. Lumin. 60&61, 324-326 (1994).
37. Time-resolved electronic Raman measurements in germanium by 100 fs Ti:Al 2 O 3 laser
K. Tanaka, H. Ohtake, and T. Suemoto
J. Lumin. 60&61, 716-719 (1994).
38. Interpretation of the temperature dependence of the luminescence intensity, lifetime, and decay profiles
in porous Si
T. Suemoto, K. Tanaka, and A. Nakajima
Phys. Rev. B 49, 11005-11009 (1994).
39. Luminescence Spectroscopy of Porous Si by Selective Excitation
T. Suemoto, K. Tanaka, and A. Nakajima
in "Light Emission from Novel Silicon Materials",
J. Phys. Soc. Jpn. 63, Suppl. B 190-202 (1994).
40. Resonance Raman scattering and its annealing effect for photo-induced defect states in quasi-onedimensional mixed-valence compound [Pt(en) 2 ][Pt(en) 2 Cl 2 ](ClO 4 ) 4
J. Takeda, M. Okada, K. Tanaka, T. Suemoto, and S. Kurita

Mol. Cryst. Liq. Cryst. 256, 873-878 (1994).
41. Resonant inter-valence-band Raman scattering of photoexcited holes in germanium
K. Tanaka, H. Ohtake, and T. Suemoto
Phys. Rev. B 50, 10694-10701 (1994).
42. Resonant Secondary Emission and Its Excitation Energy Dependence in Monoclinic Zinc Diphosphide
O. Arimoto, M. Sugisaki, K. Nakamura, K. Tanaka, and T. Suemoto
J. Phys. Soc. Jpn. 63, 4249-4255 (1994).
43. Role of alkali ions on persistent hole-burning in Pr3+-Doped Germanate Glasses
T. Suemoto, M. Namiki, and K. Koyama
Optics Commun. 115, 475-479 (1995).
44. Subpicosecond hot-hole relaxation in germanium studied by time-resolved inter-valence-band Raman
scattering
K. Tanaka, H. Ohtake, H. Nansei, and T. Suemoto
Phys. Rev. B 52, 10709-10712 (1995).
45. Emission from the Higher Members of Exciton (n = 2, 3 and 4) in β-ZnP 2
M. Sugisaki, M. Nishikawa, O. Arimoto, K. Nakamura, K. Tanaka, and T. Suemoto
J. Phys. Soc. Jpn. 64, 3506-3513 (1995).
46. Resonance Raman enhancement for photoinduced polaronic states of a quasi-one-dimensional mixedvalence platinum complex
J. Takeda, M. Okada, S. Kurita, K. Tanaka, and T. Suemoto
Phys. Rev. B 52, 14441-14444 (1995).
47. Observation of Two Types of Spectral Holes in MgO-doped Y 2 O 3 :Pr3+ Crystals
T. Okuno, K. Tanaka, and T. Suemoto
Optics Commun. 123, 512-516 (1996).
48. Observation of two types of spectral holes in Eu3+ doped β"-alumina
K. Koyama and T. Suemoto
J. Lumin. 66&67, 164-168 (1995).
49. Two types of spectral holes in Y 2 O 3 :Pr3+ crystalline systems
T. Okuno and T. Suemoto
J. Lumin. 66&67, 179-183 (1996).
50. Electronic Raman scattering of photoexcited electrons in germanium.
H. Ohtake, K. Tanaka, T. Tsukamoto, and T. Suemoto
J. Phys. Soc. Jpn. 65, 622-626 (1996).
51. Coherent optical process of 1s ortho-excitons in Cu 2 O by two-photon excitations
S. Kono, N. Naka, M. Hasuo, S. Saito, T. Suemoto, and N. Nagasawa
Solid State Commun. 97, 455-458 (1996).
52. Ultrafast electronic raman spectroscopy in semiconductors
T. Suemoto, K. Tanaka, and H. Ohtake
Prog. Crystal Growth and Charact. 33, 57-63 (1996).
53. Two kinds of spectral holes burned in Eu3+ doped β"-alumina
K. Koyama and T. Suemoto
Prog. Crystal Growth and Charact. 33, 145-148 (1996).
54. Comment on "Resonantly excited photoluminescence spectra of porous silicon"
T. Suemoto and A. Saito

Phys. Rev. B 55, 10115-10116 (1997).
55. Luminescence in selectively excited germanium microcrystallites
A. Saito and T. Suemoto
Phys. Rev. B 56, R1688-1691 (1997).
56. Resonance Raman scattering for mid-gap absorption bands in halogen-doped MX chains
J. Takeda, Y. Tsunashima, S. Kurita, S. Saito, and T. Suemoto
Synth. Met. 86, 1927-1928 (1997).
57. Defect-induced persistent hole burning in MgO-doped Pr3+:YAG systems
T. Suemoto, T. Okuno, and D. Nakano
Optics Commun. 145, 113-118 (1998).
58. Femtosecond Dynamics of the Exciton Self-Trapping Process in a Quasi-One-Dimensional HalogenBridged Platinum Complex
S. Tomimoto, H. Nansei, S. Saito, T. Suemoto, J. Takeda, and S. Kurita
Phys. Rev. Lett. 81, 417-420 (1998).
59. Mapping of site distribution in Eu3+:YAlO 3 on RF-optical frequency axes by using double-resonancespectroscopy
M. Yamaguchi, K. Koyama, T. Suemoto, and M. Mitsunaga
J. Lumin. 76&77, 681-684 (1998).
60. Femtosecond luminescence of nonequilibrium carriers in InAs
T. Suemoto, H. Nansei, S. Tomimoto, and S. Saito
J. Lumin. 76&77, 141-144 (1998).
61. Ultrafast self-trapping dynamics of excitons in quasi-one-dimensional halogen-bridged platinumcomplex
S. Tomimoto, H. Nansei, S. Saito, T. Suemoto, J. Takeda, and S. Kurita
J. Lumin. 76&77, 491-494 (1998).
62. Systematic control of spectral hole burning and homogeneous linewidth by disorder in Y 2 O 3 :Pr3+
crystalline systems
T. Okuno and T. Suemoto
Phys. Rev. B 59, 9078-9087 (1999).
63. Femtosecond luminescence from partly redistributed nonequilibrium electrons in InAs
H. Nansei, S. Tomimoto, S. Saito, and T. Suemoto
Phys. Rev. B 59, 8015-8018 (1999).
64. Perturbed ion sites in Eu3+:YAlO 3 studied by optical-rf double-resonance spectroscopy
M. Yamaguchi, K. Koyama, T. Suemoto, and M. Mitsunaga
Phys Rev. B 59, 9126-9131 (1999).
65. Observation of the wave-packet oscillation during the exciton self-trapping process in a quasi-onedimensional halogen-bridged Pt complex
S. Tomimoto, S. Saito, T. Suemoto, K. Sakata, J. Takeda, and S. Kurita
Phys. Rev. B 60, 7961-7965 (1999).
66. Femtosecond dynamics of self-trapped excitons in quasi-one-dimensional halogen-bridged Pt
complexes
T. Suemoto and S. Tomimoto
J. Lumin. 83-84, 13-18 (1999).
67. High collection efficiency in fluorescence microscopy with a solid immersion lens

K. Koyama, M. Yoshita, M. Baba, T. Suemoto, and H. Akiyama
Appl. Phys. Lett. 75 1667-1669, (1999).
68. Observation of the wave packet transit on the adiabatic potential surface of self-trapped excitons in
halogen-bridged Pt complexes
T. Suemoto, S. Tomimoto, S. Saito, K. Sakata, J. Takeda, and S. Kurita
J. Lumin. 87-89, 844-846 (2000).
69. Photo-doped carrier dynamics by two-color pump-probe time-resolved Raman scattering measurement
in Ge
S. Saito and T. Suemoto
J. Lumin. 87-89, 920-922 (2000).
70. Observation of coherent plasma-phonon coupled mode in InAs
H. Kamioka, S. Saito, and T. Suemoto
J. Lumin. 87-89, 923-926 (2000).
71. Femtosecond optical Kerr gate fluorescence spectroscopy for ultrafast relaxation processes
J. Takeda, K. Nakajima, S. Kurita, S. Tomimoto, S. Saito, and T. Suemoto
J. Lumin. 87-89, 927-929 (2000).
72. Three-parameter mapping of site distribution by optical-RF double resonance in Eu3+:Y 2 O 3 crystals
M. Yamaguchi, K. Koyama, and T. Suemoto
J. Lumin. 87-89, 1099-1101 (2000).
73. Inter-valence-band electronic Raman scattering due to photoexcited holes in Ge 1−xSi x
E. Nazvanova, T. Suemoto, S. Maruyama, and Y. Takano
Phys. Rev. B 62, 1873-1877 (2000).
74. Time-resolved luminescence spectroscopy by the optical Kerr-gate method applicable to ultrafast
relaxation processes
J. Takeda, K. Nakajima, S. Kurita, S. Tomimoto, S. Saito, and T. Suemoto
Phys. Rev. B 62, 10083-10087 (2000).
75. Selective resonance effect of the folded longitudinal phonon modes in the Raman spectra of SiC
T. Tomita, S. Saito, M. Baba, M. Hundhausen, T. Suemoto, and S. Nakashima
Phys. Rev. B 62, 12896-12901 (2000).
76. Raman intensity profiles of folded longitudinal phonon modes in SiC polytypes
S. Nakashima, H. Harima, T. Tomita, and T. Suemoto
Phys. Rev. B 62, 16605-16611 (2000).
77. Inter-conduction band electron relaxation dynamics in 6H-SiC
T. Tomita, S. Saito, T. Suemoto, H. Harima, and S. NakashimaAppl. Phys. Lett. 79, 1279-1281 (2001).
78. Temperature dependence of near ultraviolet photoluminescence in ZnO/(Mg,Zn)O multiple quantum
wells
T. Makino, N. T. Tuan, H. D. Sun, C. H. Chia, Y. Segawa, M. Kawasaki, A. Ohtomo, K. Tamura,T. Suemoto, H. Akiyama, M. Baba, S. Saito, T. Tomita, and H. Koinuma
Appl. Phys. Lett. 78, 1979-1981 (2001).
79. Pseudo gap and its relation to anomalous features in underdoped Bi2212
L. H. Machtoub, L. Robinson, J. Shimoyama, T. Suemoto, and K. Kishio
J. Raman Spectrosc. 32, 937-941 (2001).
80. The real-time observation of a coherent magnetic oscillation in NaV 2 O 5

H. Kamioka, S. Saito, M. Isobe, Y. Ueda, and T. Suemoto
J. Lumin. 94-95, 597-600 (2001).
81. Femtosecond relaxation dynamics of excitons in 1D CDW systems
S. Tomimoto, S. Saito, T. Suemoto, J. Takeda, and S. Kurita
J. Lumin. 94-95, 653-657 (2001).
82. Bridging-halogen dependence of ultrafast dynamics of excitons in quasi-one-dimensional platinumcomplexes
S. Tomimoto, S. Saito, T. Suemoto, K. Sakata, J. Takeda, and S. Kurita
International Journal of Modern Physics B 15, 3981-3984 (2001).
83. Raman scattering under hydrostatic pressures in layered BiI 3 and SbI 3 crystals
A. Saitoh, T. Komatsu, T. Karasawa, H. Ohtake, and T. Suemoto
Phys. Stat. Solidi (b) 226, 357-367 (2001).
84. Coherent magnetic oscillation in the spin ladder system α'-NaV 2 O 5
H. Kamioka, S. Saito, M. Isobe, Y. Ueda, and T. Suemoto
Phys. Rev. Lett. 88, 127201 (2002).
85. Resonance Raman and quasi-particle dynamics investigated in underdoped Bi2212
L. H. Machtoub, T. Suemoto, J. Shimoyama, and K. Kishio
J. Phys. Chem. Solids 63, 1077-1080 (2002).
86. Relaxation study of elementary excitations in Bi2212 investigated by picosecond Raman spectroscopy
L. H. Machtoub, T. Suemoto, J. Shimoyama, and K. Kishio
J. Raman Spectrosc. 33, 471-474 (2002).
87. Relaxation dynamics in photo-excited halogen-bridged Pt-complexes studied by femtosecond
luminescence spectroscopy
T. Suemoto and S. Tomimoto
Phase Transitions 75, 787-797 (2002).
88. Femtosecond dynamics of the photo-induced lattice rearrangements in quasi-one-dimensional halogenbridged platinum complexes
T. Suemoto, S. Tomimoto, and T. Matsuoka
in "Photoinduced Phase Transitions", ed. by K. Nasu (World Scientific, 2002) 161-191.
89. Overtone modulation and anti-phasing behavior of wave-packet amplitudes on the adiabatic potential
surface of self-trapped excitons
T. Matsuoka, S. Saito, J. Takeda, S. Kurita, and T. Suemoto
Nonlinear Optics 29, 587-593 (2002).
90. Ultrafast dynamics of lattice relaxation of excitons in quasi-one-dimensional halogen-bridged platinumcomplexes
S. Tomimoto, S. Saito, T. Suemoto, J. Takeda, and S. Kurita
Phys. Rev. B 66, 155112 (2002).
91. Nature of the Inhomogeneous Broadening of Optical Spectra in Eu3+ doped Y 2 O 3 Crystals Studied by
Optical-RF Double Resonance
M. Yamaguchi and T. Suemoto
J. Phys. Soc. Jpn. 72, 429-436 (2003).
92. Real-time capturing of the nuclear wave-packet shape in self-trapped excitons
T. Matsuoka, J. Takeda, S. Kurita, and T. Suemoto
Phys. Rev. Lett. 91, 247402 (2003).

93. Magnetic excitations investigated by ultrashort pulse excitation in high-T c superconductors
L. H. Machtoub, T. Suemoto, J. Shimoyama, and K. Kishio
Physica C 388-389, 317-318 (2003).
94. Elementary excitations investigated by femtosecond Raman spectroscopy in underdoped cuprates
L. H. Machtoub, G. El Machtoub, J. Shimoyama, T. Suemoto, and K. kishio
Physica C 392-396, 291-294 (2003).
95. J band luminescence observed with excitation below the band-gap energy on cyanine J aggregate
S. Kurita, T. Honma, H. Nakamura, T. Sekiya, M. Nakajima, and T. Suemoto
J. Lumin. 108, 15-18 (2004).
96. Nuclear wave-packet dynamics in the localized excitons of halogen-bridged platinum complexes
T. Suemoto, T. Matsuoka, J. Takeda, and S. Kurita
J. Lumin. 108, 167-171 (2004).
97. Structure dependent ultrafast relaxation time of photo-excited carriers in SiC
T. Tomita, S. Saito, T. Suemoto, H. Harima, and S. Nakashima
J. Phys. Soc. Jpn. 73 2554-2561 (2004).
98. Evidence for an excited state with a large lattice relaxation in quasi-one-dimensional halogen-bridged
Ni complexes
Y. Takahashi and T. Suemoto
Phys. Rev. B 70, 081101(R) (2004).
99. Competing terahertz radiation mechanisms in semi-insulating InP at high-density excitation
M. Nakajima, Y. Oda, and T. SuemotoAppl. Phys. Lett. 85, 2694-2696 (2004).
100. Polarity reversal of the magnetic field induced component of terahertz radiation from InAs surfaces athigh density excitation
M. Nakajima, Y. Oda, T. Suemoto, and S. Saito
Appl. Phys. Lett. 85, 4597-4599 (2004).
101. Transient phase change induced by femtosecond light pulses in the spin ladder system α'-NaV 2 O 5
T. Suemoto, M. Nakajima, M. Aiba, M. Isob, and Y. Ueda
Solid State Commun. 132, 577-581 (2004).
102. Photo-induced phase transition in the 2D spin ladder compound NaV 2 O 5
M. Aiba, M. Nakajima, M. Isobe, Y. Ueda, and T. Suemoto
J. Lumin. 112, 246-249 (2005).
103. Excited state dynamics in quasi-one-dimensional nickel complexes studied by femtosecond
luminescence spectroscopy
Y. Takahashi, T. Matsuoka, K. Yasukawa, and T. Suemoto
J. Lumin. 112, 255-258 (2005).
104. Up-converted luminescence on cyanine dye J-aggregates
K. Miyasue, T. Honma, S. Kurita, T. Sekiya, M. Nakajima, and T. Suemoto
J. Lumin. 112, 416-419 (2005).
105. Ultrafast dynamics of photoinduced phenomena in the spin ladder system NaV 2 O 5
T. Suemoto, M. Nakajima, K. Kazumi, H. Nagase, M. Aiba, M. Isobe, and Y. Ueda
J. Phys.: Conference Series 21, 15-22 (2005).
106. Time-resolved Raman spectroscopy applied to the photo-induced phenomena in NaV 2 O 5
M. Nakajima, K. Kazumi, M. Isobe, Y. Ueda, and T. Suemoto

J. Phys.: Conference Series 21, 201–206 (2005).
107. Wave-packet oscillation in the excited state of KBr F centers
T. Koyama, Y. Takahashi, M. Nakajima, and T. Suemoto
J. Lumin. 119-120, 43-46 (2006).
108. Photo-induced phenomena in NaV 2 O 5 studied by time-resolved Raman spectroscopy
M. Nakajima, K. Kazumi, M. Isobe, Y. Ueda, and T. Suemoto
J. Lumin. 119-120, 448-452 (2006).
109. Real-Time Observation on Femtosecond Depolarization of Room-Temparature Luminescence in KI F
Centers
T. Koyama, Y. Takahashi, M. Nakajima, and T. Suemoto
J. Phys. Soc. Jpn. 75, 045001 (2006).
110. Selective observation of the wave-packet dynamics in the excited states at KBr F centers byluminescence experiments
T. Koyama, Y. Takahashi, M. Nakajima, and T. Suemoto
Phys. Rev. B 73, 161102(R) (2006).
111. Persistent nuclear wave packet oscillation coexistent with incoherent vibrational population at excited
F centers in Kl
T. Koyama, Y. Takahashi, M. Nakajima, and T. Suemoto
J. Chem. Phys. 124, 221104 (2006).
112. Lissajous-like wavepacket motion on the two-dimensional adiabatic potential surface in localized
excitons
K. Yasukawa, Y. Takahashi, S. Kurita, and T. Suemoto
Solid State Commun. 140, 197–201 (2006).
113. Relaxation processes from charge-transfer excited states of organic radical 1,3,5-trithia-2,4,6triazapentalenyl crystals studied by ultrafast luminescence spectroscopy
Y. Takahashi, T. Suemoto, S. Oguri, and J. Takeda
Phys. Rev. B 74, 193104 (2006).
114. Terahertz radiation from semiconductor surfaces in magnetic fields at high-density excitation (invited)
M. Nakajima, Y. Oda, S. Saito, and T. Suemoto
Photonics West 2006, 21-26 January 2006, San Jose, USA, 6118-19.
Ultrafast Phenomena in Semiconductors and Nanostructure Materials X (SPIE, 2006) 61180J
115. Ultrafast time-resolved infrared luminescence spectroscopy in halogen-bridged Pd complexes
Y. Takahashi, H. Kitagawa, and T. Suemoto
Phys. Stat. Solidi (c) 3, 3531-3534 (2006).
116. Photoinduced phenomena observed as transient reflectance changes in α’-NaV 2 O 5
T. Suemoto, H. Nagase, M. Nakajima, M. Isobe, and Y. Ueda
Phys. Stat. Solidi (c) 3, 3452-3455 (2006).
117. Excited-state dynamics of TTTA studied by femtosecond luminescence spectroscopy
Y. Takahashi, T. Suemoto, S. Oguri, and J. Takeda
J. Lumin. 122-123, 529-531 (2007).
118. Dynamical behavior of the wave packets on adiabatic potential surfaces observed by femtosecond
luminescence spectroscopy
T. Suemoto, M. Nakajima, T. Matsuoka, Taira, K. Yasukawa, and T. Koyama
J. Lumin. 122-123, 517-521 (2007).

119. Thermal and non-thermal photoinduced phenomena in α'-NaV 2 O 5
T. Suemoto, H. Nagase, M. Nakajima, M. Isobe, and Y. Ueda
J. Phys. Condensed Matter 19, 076207 (2007).
120. Nuclear wave-packet dynamics on nearly degenerate two adiabatic potential energy surfaces intheexcited state of KI F centers
T. Koyama, Y. Takahashi, M. Nakajima, and T. Suemoto
Phys. Rev. B 76, 115122 (2007).
121. Wavepacket dynamics at low temperature in localized excitons of the quasi-one-dimensional Br-bridged
Pt complex studied by femtosecond luminescence spectroscopy
K. Yasukawa, Y. Takahashi, T. Suemoto, and S. Kurita
J. Phys. Soc. Jpn. 76, 084707 (2007).
122. Formation and photoluminescence characterization of transparent silica glass prepared by solid-phasereaction of nanometer-sized silica particles
T. Yamada, M. Nakajima, T. Suemoto, and T. Uchino
J. Phys. Chem. C 111, 12973-12979 (2007).
123. Photoinduced metallic state in VO 2 proved by the terahertz pump-probe spectroscopy
M. Nakajima, N. Takubo, Z. Hiroi, Y. Ueda, and T. SuemotoAppl. Phys. Lett. 92, 011907 (2008).
124. Microfluidic Synthesis-induced Luminescence of C 60 Rods
K. Shinohara, S. Someya, H. Abe, T. Suemoto, and K. Okamoto
Chem. Lett. 37, 358-359 (2008).
125. Wavepacket Motion in Self-trapped Exciton of a Quasi-One-Dimensional Halogen-bridged Pt
Complex, [Pt(en) 2 ][Pt(en) 2 I 2 ] (ClO 4 ) 4 , Observed by Femtosecond Time Resolved Luminescence
Spectroscopy
K. Yasukawa, Y. Takahashi, S. Kurita, and T. Suemoto
J. Phys. Soc. Jpn. 77, 064714 (2008).
126. Ultrafast dynamical study of self-trapped excitons in ladder type of halogen-bridged Pt complexes
T. Suemoto, Y. Takahashi, K. Yasukawa, D. Kawakami, S. Takaishi, M. Yamashita, A. Kobayashi,
and H. Kitagawa
J. Lumin. 128, 1081-1083 (2008).
127. Ultrafast time-resolved spectroscopy of the spin-Peierls compound CuGeO 3
Y. Yuasa, M. Nakajima, T. Yamanouchi, Y. Ueda, and T. Suemoto
J. Lumin. 128,1087-1089 (2008).
128. Nuclear wave-packet oscillations at the F center in KCl and RbCl
T. Koyama, M. Nakajima, and T. Suemoto
Phys. Rev. B 78, 155126 (2008).
129. Temperature dependence of photoinduced valence changes in rubidium manganese hexacyanoferrate
probed by Raman spectroscopy
R. Fukaya, M. Nakajima, H. Tokoro, S. Ohkoshi, and T. Suemoto
J. Phys.: Conference Series 148, 012030 (2009).
130. Dynamics of nuclear wave packet in the excited state of KCl F centers
T. Koyama, M. Nakajima, and T. Suemoto
Phys. Stat. Solidi (c) 6, 108 - 111 (2009).
131. Propagation of a ballistic nuclear wavepacket on an adiabatic potential surface of a one-dimensional Br-

bridged Pd complex without a self-trapped exciton state
Y. Takahashi, H. Kitagawa, and T. Suemoto
Phys. Rev. B 79, 153103 (2009).
132. Dynamics of the charge transferred states relevant to magnetic phase transition in rubidium manganesehexacyanoferrate
T. Suemoto, K. Ohki, R. Fukaya, M. Nakajima, H. Tokoro, and S. Ohkoshi
J. Lumin. 129, 1775–1778 (2009).
133. Second 2s-2p level crossing at the F center in KCl evidenced by frequency upconversion spectroscopy
T. Koyama, M. Nakajima, and T. Suemoto
Phys. Rev. B 79, 193103 (2009).
134. Synthesis of an Electromagnetic Wave Absorber for High-Speed Wireless Communication
A. Namai, S. Sakurai, M. Nakajima, T. Suemoto, K. Matsumoto, M. Goto, S. Sasaki,
and S. Ohkoshi
J. Am. Chem. Soc. 131, 1170-1173 (2009).
135. Observation of nuclear wave packets in the excited state of the F-center in alkali halides
T. Koyama, M. Nakajima, and T. Suemoto
J. Lumin. 129, 1435-1440 (2009).
136. Study of photo-induced phenomena in VO 2 by terahertz pump-probe spectroscopy
M. Nakajima, N. Takubo, Z. Hiroi, Y. Ueda, and T. Suemoto
J. Lumin. 129, 1802-1805 (2009).
137. Photoinduced charge-transfer process in rubidium manganese hexacyanoferrate probed by Raman
spectroscopy
R. Fukaya, M. Nakajima, H. Tokoro, S. Ohkoshi, and T. Suemoto
J. Chem. Phys. 131, 154505 (2009).
138. Splitting dynamics of nuclear wave packets in a Peierls insulator using femtosecond laser spectroscopy
Y. Takahashi, K. Yasukawa, S. Kurita, and T. Suemoto
Phys. Rev. B 81, 081102(R) (2010).
139. Single-shot picosecond interferometry with one-nanometer resolution for dynamical surface
morphology using a soft X-ray laser
T. Suemoto, K. Terakawa, Y. Ochi, T. Tomita, M. Yamamoto, N. Hasegawa, M. Deki, Y. Minami,
and T. Kawachi
Opt. Exp. 18, 14114-14122 (2010).
140. Ultrafast time domain demonstration of bulk magnetization precession at zero magnetic field
ferromagnetic resonance induced by terahertz magnetic field
M. Nakajima, A. Namai, S. Ohkoshi, and T. Suemoto
Opt. Exp. 18, 18260-18268 (2010).
141. Coherent Control of Spin Precession Motion with Impulsive Magnetic Fields of Half-Cycle Terahertz
Radiation
K. Yamaguchi, M. Nakajima, and T. Suemoto
Phys. Rev. Lett. 105, 237201 (2010).
142. Photo-induced phase switching dynamics in RbMn[Fe(CN) 6 ] probed by accumulation free mid-infrared
spectroscopy
A. Asahara, M. Nakajima, R. Fukaya, H. Tokoro, S. Ohkoshi, and T. Suemoto
Phys. Stat. Solidi B 248, 491–494 (2011).

143. Dynamics of photoinduced phase transitions in hexacyanoferrate studied by infrared and Raman
spectroscopy
T. Suemoto, R. Fukaya, A. Asahara, M. Nakajima, H. Tokoro, and S. Ohkoshi
Phys. Stat. Solidi B 248, 477–481 (2011).
144. Observation of ultrafast Q-band fluorescence in horse heart cytochrome c in reduced and oxidized forms
T. Suemoto, H. Ebihara, H. Nakao, and M. Nakajima
J. Chem. Phys. 134, 034502 (2011).
145. Effect of preformed plasma on terahertz-wave emission from the plasma generated by two-color laser
pulsesY. Minami, M. Nakajima, and T. Suemoto
Phys. Rev. A 83, 023828 (2011).
146. Dynamics of nuclear wave packets at the F center in alkali halides (review)
T. Koyama and T. Suemoto
Rep. Prog. Phys. 74, 076502 (2011).
147. Non-thermal hot electrons ultrafastly generating hot optical phonons in graphite
Y. Ishida, T. Togashi, K. Yamamoto, M. Tanaka, T. Taniuchi, T. Kiss, M. Nakajima, T. Suemoto,and S. Shin
Sci. Rep. 1, 64 (2011).
148. Time-resolved luminescence spectroscopy of self-trapped excitons in ladder type Br-bridged Pt
complexes
T. Suemoto, H. Nakao, M. Nakajima, and H. Kitagawa
J. Chem. Phys. 134, 224503 (2011).
149. Effect of lattice deformation on photoinduced phase transition process in RbMn[Fe(CN) 6 ]R. Fukaya, M. Nakajima, H. Tokoro, S. Ohkoshi, and T. Suemoto
Phys. Stat. Solidi B 248, 482-485 (2011).
150. Picosecond Soft-X-ray Laser Interferometer for Probing Nanometer Surface Structure
Y. Ochi, K. Terakawa, N. Hasegawa, M. Yamamoto, T. Tomita, T. Kawachi, Y. Minami,
M. Nishikino, T. Imazono, M. Ishino, and T. Suemoto
Jpn. J. Appl. Phys. 51, 016601 (2012).
151. Ultrafast Coherent Control of Spin Precession Motion by Terahertz Magnetic Pulses
M. Nakajima, K. Yamaguchi, and T. SuemotoActa Physica Polonica A 121, 343-346 (2012).
152. Growth Dynamics of Photoinduced Phase Domain in Cyano-Complex Studied by Boundary Sensitive
Raman Spectroscopy
A. Asahara, M. Nakajima, R. Fukaya, H. Tokoro, S. Ohkoshi, and T. SuemotoActa Physica Polonica A 121, 375-378 (2012).
153. Anomalous behavior of high-frequency zero-field ferromagnetic resonance in aluminum-substituted εFe 2 O 3
M. Yoshikiyo, A. Namai, M. Nakajima, T. Suemoto, and S. Ohkoshi
J. Appl. Phys. 111, 07A726 (2012).
154. Hard magnetic ferrite with a gigantic coercivity and high frequency millimetre wave rotation
A. Namai, M. Yoshikiyo, K. Yamada, S. Sakurai, T. Goto, T. Yoshida, T. Miyazaki, M. Nakajima,
T. Suemoto, H. Tokoro, and S. OhkoshiNat. Commun. 3, 1035 (2012).

155. Pulsed laser ablation plasmas generated in CO 2 under high-pressure conditions up to supercritical fluid
T. Kato, S. Stauss, S. Kato, K. Urabe, M. Baba, T. Suemoto, and K. TerashimaAppl. Phys. Lett. 101, 224103 (2012).
156. Experimental veriﬁcation of femtosecond laser ablation schemes by time-resolved soft x-ray reﬂective
imaging
T. Tomita, M. Yamamoto, N. Hasegawa, K. Terakawa, Y. Minami, M. Nishikino, M. Ishino,
T. Kaihori, Y. Ochi, T. Kawachi, M. Yamagiwa, and T. Suemoto
Opt. Exp. 20, 29329-29337 (2012).
157. Ultrafast dynamics of reversible photoinduced phase transitions in rubidium manganesehexacyanoferrate investigated by midinfrared CN vibration spectroscopy
A Asahara, M Nakajima, R Fukaya, H Tokoro, S. Ohkoshi, and T. Suemoto
Phys. Rev. B 86, 195138 (2012).
158. Mechanism of Enhanced Optical Second-Harmonic Generation in the Conducting Pyrochlore-Type
Pb 2 Ir 2 O 7−x Oxide Compound
Y. Hirata, M. Nakajima, Y. Nomura, H. Tajima, Y. Matsushita, K. Asoh, Y. Kiuchi, A. G. Eguiluz,
R. Arita, T. Suemoto, and K. Ohgushi
Phys. Rev. Lett. 110, 187402 (2013).
159. The synthesis of rhodium substituted ε-iron oxide exhibiting super high frequency natural resonance
A. Namai, M. Yoshikiyo, S. Umeda, T. Yoshida, T. Miyazaki, M. Nakajima, K. Yamaguchi,
T. Suemoto, and S. Ohkoshi
J. Mater. Chem. C 1, 5200-5206 (2013).
160. Terahertz Time-Domain Observation of Spin Reorientation in Orthoferrite ErFeO 3 through Magnetic
Free Induction Decay
K. Yamaguchi, T. Kurihara, Y. Minami, M. Nakajima, and T. Suemoto
Phys. Rev. Lett. 110, 137204 (2013).
161. Access to hole dynamics in graphite by femtosecond luminescence and photoemission spectroscopy
T. Suemoto, S. Sakaki, M. Nakajima, Y. Ishida, and S. Shin
Phys. Rev. B 87, 224302 (2013).
162. Probing of local structures of thermal and photoinduced phases in rubidium manganesehexacyanoferrate by resonant Raman spectroscopy
R. Fukaya, A. Asahara, S. Ishige, M. Nakajima, H. Tokoro, S. Ohkoshi, and T. Suemoto
J. Chem. Phys. 139, 084303 (2013).
163. High-power THz wave generation in plasma induced by polarization adjusted two-color laser pulses
Y. Minami, T. Kurihara, K. Yamaguchi, M. Nakajima, and T. SuemotoAppl. Phys. Lett. 102, 041105 (2013).
164. Longitudinal terahertz wave generation from an air plasma filament induced by a femtosecond laser
Y. Minami, T. Kurihara, K. Yamaguchi, M. Nakajima, and T. SuemotoAppl. Phys. Lett. 102, 151106 (2013).
165. Dielectric probe for scattering-type terahertz scanning near-field optical microscopy
T. Kurihara, K. Yamaguchi, H. Watanabe, M. Nakajima, and T. SuemotoAppl. Phys. Lett. 103, 151105 (2013).
166. Dynamics of pulsed laser ablation in high-density carbon dioxide including supercritical fluid state
K. Urabe, T. Kato, S. Stauss, S. Himeno, S. Kato, H. Muneoka, M. Baba, T. Suemoto,and K. Terashima

Appl. Phys. Lett. 114, 143303 (2013).
167. Domain growth and aggregation dynamics in photo-induced phase transition phenomena
H. Watanabe, S. Ishige, A. Asahara, H. Tokoro, S. Ohkoshi, and T. Suemoto
J. Lumin. 152, 108-111 (2014).
168. Ultrafast dynamics of photoinduced semiconductor-to-metal transition in the optical switching nanooxide Ti 3 O 5
A. Asahara, H. Watanabe, H. Tokoro, S. Ohkoshi and T. Suemoto
Phys. Rev. B 90, 014303 (2014).
169. Spectral dynamics of picosecond gain-switched pulses from nitride-based vertical-cavity surfaceemitting lasers
S. Chen, T. Ito, A. Asahara, M. Yoshita, W. Liu, J. Zhang, B. Zhang, T. Suemoto, and H. Akiyama
Sci. Rep. 4, 4325 (2014).
170. Gain-switching dynamics in optically pumped single-mode InGaN vertical-cavity surface-emitting
lasersS. Chen, A. Asahara, T. Ito, J. Zhang, B. Zhang, T. Suemoto, M. Yoshita, and H. Akiyama
Opt. Exp. 22, 4196-4201 (2014).
171. Submicron scale image observation with a grazing incidence reflection-type single-shot soft X-ray
microscope
M. Baba, M. Nishikino, N. Hasegawa, T. Tomita, Y. Minami, R. Takei, M. Yamagiwa, T. Kawachi,
and T. Suemoto
Jpn J. App. Phys. 53, 080302 (2014).
172. Enhanced spin-precession dynamics in a spin-metamaterial coupled resonator observed in terahertz
time-domain measurements
T. Kurihara, K. Nakamura, K. Yamaguchi, Y. Sekine, Y. Saito, M. Nakajima, K. Oto, H. Watanabe,
and T. Suemoto
Phys. Rev. B 90, 144408 (2014).
173. Time-Resolved Soft X-Ray Imaging of Femtosecond Laser Ablation Processes on Metals
T. Tomita, M. Nishikino, N. Hasegawa, Y. Minami, R. Takei, M. Baba, T. Eyama, S. Takayoshi,
T. Kaihori, T. Morita, Y. Hirano, T. Kawachi, M. Yamagiwa, and T. Suemoto
J. Laser Micro Nanoengineering 9, 137-142 (2014).
174. Nonlinear photoluminescence properties of trions in hole-doped single-walled carbon nanotubes
N. Akizuki, M. Iwamura, S. Mouri, Y. Miyauchi, T. Kawasaki, H. Watanabe, T. Suemoto,
K. Watanabe, K. Asano, and K. Matsuda
Phys. Rev. B 89, 195432 (2014).
175. High-frequency millimeter wave absorption of indium-substituted ε-Fe 2 O 3 spherical nanoparticles(invited)
M. Yoshikiyo, A. Namai, M. Nakajima, K. Yamaguchi, T. Suemoto, and S. Ohkoshi
J. Appl. Phys. 115, 172613 (2014).
176. Direct generation of 2-ps blue pulses from gain-switched InGaN VCSEL assessed by up-conversion
technique
A. Asahara, S. Chen, T. Ito, M. Yoshita, W. Liu, B. Zhang, T. Suemoto, and H. Akiyama
Sci. Rep. 4, 6401 (2014).
177. Ultraviolet stimulated emission from high-temperature-annealed MgO microcrystals at room
temperature

H. Soma, Y. Uenaka, A. Asahara, T. Suemoto, and T. UchinoAppl. Phys. Lett. 106, 041116 (2015).
178. Magnetization-free measurements of spin orientations in orthoferrites using terahertz time domain
spectroscopy
T. Suemoto, K. Nakamura, T. Kurihara, and H. WatanabeAppl. Phys. Lett. 107, 042404 (2015).
179. Dynamics of photoinduced change of magnetoanisotropy parameter in orthoferrites probed withterahertz excited coherent spin precession
K. Yamaguchi, T. Kurihara, H. Watanabe, M. Nakajima, and T. Suemoto
Phys. Rev. B 92, 064404 (2015).
180. Layer number dependence of carrier lifetime in graphenes observed using time-resolved mid-infrared
luminescence
H. Watanabe, T. Kawasaki, T. Iimori, F. Komori, and T. Suemoto
Chem. Phys. Lett. 637, 58-62 (2015).
181. Optically detecting the edge-state of a three-dimensional topological insulator under ambient conditions
by ultrafast infrared photoluminescence spectroscopy
S. Maezawa, H. Watanabe, M. Takeda, K. Kuroda, T. Someya, I. Matsuda, and T. Suemoto
Sci. Rep. 5, 16443 (2015).
182. Magnetic-excitation-assisted photoluminescence from self-trapped exciton states in MnO
J. Nishitani, T. Nagashima, and T. Suemoto
J. Phys.: Condens. Matter 28, 016004 (2016).
183. Dynamics of photoinduced phase transitions in a Prussian blue analog studied by CN vibrational
spectroscopy (review)
T. Suemoto, R. Fukaya, A. Asahara, H. Watanabe, H. Tokoro, and S. Ohkoshi
Current Inorganic Chemistry, 6, 10-25 (2016).
184. Investigation of insulator-metal transition in Ti 4 O 7 using terahertz probe pulse
H. Kamioka, J. Nishitani, H. Tsukada, R. Yamaguchi, and T. SuemotoAppl. Phys. Lett. 108, 071908 (2016).
185. Optical pump-terahertz probe analysis of long-lived d-electrons and relaxation to self-trapped exciton
states in MnO
J. Nishitani, T. Nagashima, M. Lippmaa, and T. SuemotoAppl. Phys. Lett. 108, 162101 (2016).
186. Formation of x-ray Newton’s rings from nano-scale spallation shells of metals in laser ablation
Masaharu Nishikino, Noboru Hasegawa, Takuro Tomita, Yasuo Minami, Takashi Eyama, Naoya
Kakimoto, Rui Izutsu, Motoyoshi Baba, Tetsuya Kawachi, and Tohru Suemoto
AIP Advances 7, 015311 -1-5 (2017)187. Observation of long-lived coherent spin precession in orthoferrite ErFeO3 induced by terahertz
magnetic fields
Hiroshi Watanabe, Takayuki Kurihara, Takeo Kato, Keita Yamaguchi, and Tohru SuemotoAppl. Phys. Lett. 111, 092401 (2017)188. Observation of fs-laser spallative ablation using soft X-ray laser probe
Masaharu Nishikino, Noboru Hasegawa, Takuro Tomita, Yasuo Minami, Takeshi Eyama, Naoya
Kakimoto, Rui Izutsu, Motoyoshi Baba, Tetsuya Kawachi and Tohru Suemoto
Proc. of SPIE Vol. 10091, 100910O-1 (2017).

189. Purely excitonic lasing in ZnO microcrystals: Temperature-induced transition between exciton-excitonand exciton-electron scattering
Ryosuke Matsuzaki, Haruka Soma, Kanae Fukuoka, Kanako Kodama, Akifumi Asahara, Tohru
Suemoto, Yutaka Adachi and Takashi Uchino
Phys. Rev. B 96, 125306 (2017).
190. Coherent Two-Dimensional Terahertz Magnetic Resonance Spectroscopy of Collective Spin Waves
Jian Lu, Xian Li, Harold Y. Hwang, Benjamin K. Ofori-Okai, Takayuki Kurihara, Tohru Suemoto andKeith A. Nelson
Phys. Rev. Lett. 118, 207204 (2017).
191. Rarefaction after fast laser heating of a thin metal film on a glass mount
N. A. Inogamov, V. A. Khokhov, Y. V. Petrov, V. V. Zhakhovsky, K. P. Migdal, D. K. Ilnitsky, N.
Hasegawa, M. Nishikino, M. Yamagiwa, M. Ishino, T. Kawachi, A. Y. Faenov, T. A. Pikuz, M. Baba,
Y. Minami, and T. Suemoto
AIP Conference Proceedings 1793, 070012 (2017).
192. Macroscopic magnetization control by symmetry breaking of photoinduced spin reorientation withintense terahertz magnetic-nearfieldTakayuki Kurihara, Hiroshi Watanabe, Makoto Nakajima, Shutaro Karube, Kenichi Oto, YoshiChika
Otani, and Tohru Suemoto
Phys. Rev. Lett. 120, 107202-1-6 (2018).
193. Enhancing terahertz magnetic near field induced by a micro-split-ring resonator with a tapered
waveguide
Hongsong Qiu, Takayuki Kurihara, Hirofumi Harada, Kosaku Kato, Keisuke Takano, Tohru Suemoto,
Masahiko Tani, Nobuhiko Sarukura, Masashi Yoshimura, and Makoto Nakajima,
Opt. Lett. 43, 1658 (2018).