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DOI： 10.7567/APEX.9.121601

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DOI： 10.1021/acs.cgd.6b01294

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DOI： 10.1021/acs.cgd.6b01039

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DOI： 10.1088/0953-8984/28/30/304001

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DOI： 10.1039/C5TC01531F

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DOI： 10.1038/nphys3359

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DOI： 10.1246/cl.150115

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DOI： 10.7566/JPSJ.84.044715

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DOI： 10.1039/C4TC01701C

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DOI： 10.1038/ncomms6528

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DOI： 10.1021/jp506361b

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DOI： 10.7566/JPSJ.83.074708

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DOI： 10.1021/jp4093332

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DOI： 10.1246/bcsj.20130248

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1063/1.4833400

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevLett.111.197801

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/jp406650t

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevB.88.125101

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1063/1.4817546

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1063/1.4804610

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/nn305558r

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/jp312798h

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/ja309279w

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1143/JJAP.50.091602

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1143/APEX.4.031601

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.jlumin.2010.10.044

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/jz101635n

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1063/1.3486160

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.tsf.2010.08.037

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1063/1.3466916

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1063/1.3454915

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevB.80.205201

Language：English   Publishing type：Research paper (scientific journal)  

The synthesis, structure, photoelectrochemical behavior, and nonlinear optical (NLO) properties
of a symmetric acceptor-acceptor-donor-acceptor-acceptor array, C60-Co-TTF-Co-C60, have been
described. The precursors, namely, cobalt dicarbonyl complexes Co(C60Ar5)(CO)2 were synthesized from
the penta(organo)[60]fullerenes, C60Ar5H, as starting materials. In the next step, two cobalt-fullerene
complexes were connected to a tetrathiafulvalene (TTF) tetrathiolate bridge to obtain the C60-Co-TTF-Co-
C60 array. In addition, the monomeric compounds, Co(C60Ar5)(S2C2R2) (R ) CO2Me and CN) and
Co(C60Ar5)(S2C2S2 C ) CS2C2R2) were synthesized as references. The C60-Co-TTF-Co-C60 array exhibits
very strong transitions in the near-infrared region (λmax ) 1,100 nm, ε ) 30 000 M-1 ·cm-1) due to a ligandto-
metal-charge-transfer (LMCT) transition and six reversible electron transfer processes. In the crystal, a
fullerene/TTF-layered packing structure is evident. Femtosecond flash photolysis revealed that photoexcitation
of the array results in a charge separated state involving the strongly interacting cobaltadithiolene
and TTF constituents which electronically relax via a resonance effect that extends all throughout the
acceptor parts of the C60-Co-TTF-Co-C60 array. The third-order NLO measurement of the array gave the
magnitude of the third-order nonlinear susceptibility, |(3)|, values to be 9.28 × 10-12 esu, suggesting
the π-conjugation of donors and acceptors in the array.

DOI： 10.1021/ja902312q

Language：English   Publishing type：Research paper (scientific journal)  

Self-assembly of polythiophenes with C≡CR (R = alkyl, phenyl, etc.) side chains has been investigated. Seven
new polymers consisting of head-to-head and tail-to-tail 2,2¤-bithiophenes with C≡CR side chains were synthesized. The new polymers include alternating copolymers between bithiophenes with C≡C alkyl side chains and thiophene and those between bithiophenes with C≡C alkyl side chains and 2,2¤-bithiophene. The polythiophene main chain is considered to be coplanar because of the absence of steric repulsion between the main chain and the C≡CR side chain. Single-crystal X-ray crystallography and DFT calculations indicated that the head-to-head- and tail-to tail-2,2-bithiophenes with C≡CR side chains were coplanar. The polythiophenes with C≡CR side chains showed a strong tendency to selfassemble, and assumed edge-on alignment and side-on alignment on the surface of substrates. Self-assembly caused a decrease in the pi-pi* transition energy of the polymers by 0.3 0.4eV. A copolymer of thiophene and dialkoxy-pphenylene showed analogous self-assembly. The polythiophenes with C≡CR side chains showed piezochromism, with a decrease in the pi-pi* transition energy by about 0.2 eV at 10 GPa. Head-to-head-P3(C≡CDec) Th with a C≡C decyl side chain gave a larger optical third-order nonlinear susceptibility chi(3) than regio-regular poly(3-hexylthiophene)s.

DOI： 10.1246/bcsj.82.896

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

We demonstrate current oscillation phenomena using the negative differential resistance
in a one-dimensional halogen-bridged nickel compound, [Ni(chxn)2Br]Br2 (chxn
=cyclohexanediamine). By attaching external resistors and a capacitor to a [Ni(chxn)2Br]Br2
sample, we obtain stable current oscillation at 90 K. The oscillation and its period are explained by
a simple model.

DOI： 10.1063/1.3157211

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/ic901067z

Language：English   Publishing type：Research paper (scientific journal)  

Resonant behavior and magnitudes of third-order nonlinear optical susceptibilities in double-walled carbon nanotubes (DWNTs) have been investigated by means of femtosecond pump-probe spectroscopy with different pump-photon energies. With the selective excitation of the E22 exciton transition of the inner tubes labeled by the chiral vector indices (7,5) and (7,6), the imaginary part of nonlinear susceptibility Imχ(3) has shown the resonant enhancement compared with the case of the nonresonant excitation of the specific tube. The nonlinear response signal at the E22 transition energy of the (8,7) tube has been also enhanced for the excitation of the G-band phonon sideband of its E22 transition. This result is consistent with the phonon-mediated nonlinear optical process observed for the E22 transitions in single-walled carbon nanotubes (SWNTs). It has been also found that the values of the figure of merit Im χ(3)/α (α: absorption coefficient) of the inner tubes in DWNTs are smaller than those of the corresponding SWNTs, which is interpreted in terms of decay time shortening due to the energy relaxation between the inner and outer tubes.

DOI： 10.1016/j.jlumin.2009.02.027

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1073/pnas.0900155106

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.synthmet.2009.01.043

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.jlumin.2007.11.043

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

We have performed electroabsorption spectroscopy on micelle-wrapped single-wall carbon nanotubes.
In semiconducting nanotubes, many oscillating structures composed of the increase and decrease of
absorption are observed in the spectra in the region of the first and second absorption bands, E11 and E22.
The spectral shape is reproduced mainly by the second-derivative curve of the absorption spectrum, which
indicates the presence of nearly degenerate bright and dark excitonic states.

DOI： 10.1103/PhysRevLett.100.097401

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

Third-order optical nonlinearity was investigated in two charge-transfer CT-type conjugated polymers, polyaryleneethynyleneand polythiophene-alt-thiazole, using the third-harmonic
generation THG method. Comparison of the results with previously obtained THG data for
polythiophene and the strong CT polymer polythiophene-alt-quinoxaline revealed that the ratio of
the maximum value of third-order nonlinear susceptibility and the absorption coefficient
max chi(3)/alpha max increased as the degree of CT character increased for the four polymers. This
variation in max chi(3)/alpha max is discussed based on the magnitude of the transition dipole moment
between the one-photon-allowed and the one-photon-forbidden excited states.

DOI： 10.1063/1.2837643

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/nmat2067

Language：English   Publishing type：Research paper (scientific journal)  

Photoinduced phase transitions in spin-Peierls SP systems of alkali M=K,Na-tetracyanoquinodimethane
TCNQ have been studied by a reflection-type femtosecond fs pump-probe spectroscopy. The SP phase is
destabilized by the generation of photocarriers through the breaking of the spin-singlet states in dimers. It
results in the decrease of the dimeric molecular displacements within a few hundred of femtoseconds over
several tens of TCNQ molecules. It is accompanied by the displacive-type coherent oscillations, which consist
mainly of three modes with the frequencies of 20, 49, and 90 cm-1 in K-TCNQ and of two modes with the
frequencies of 49 and 99 cm-1 in Na-TCNQ. By taking into account the temperature dependence of the Raman
scattering spectra, the mode with 20 cm-1 in K-TCNQ and the modes with 49 and 99 cm-1 in Na-TCNQ are
assigned to the phonon modes in the SP ground state, while the modes with 49 and 90 cm-1 in K-TCNQ are
assigned to the local modes originating from the photoexcited states. Polarization dependence of the Raman
scattering signals shows that the 20-cm-1 mode of K-TCNQ and the 49-cm-1 mode of Na-TCNQ are longitudinal
optical LO modes, whereas the 99-cm-1 mode of Na-TCNQ is a transverse optical TO mode.
Namely, the LO mode plays an important role on the stabilization of the SP phase in K-TCNQ, while both the
LO and TO modes in Na-TCNQ. Such a difference is discussed by scrutinizing the difference of the crystal
structures and the nature of the SP transitions in the two compounds.

DOI： 10.1103/PhysRevB.76.085106

Language：English   Publishing type：Research paper (scientific journal)  

The head-to-head-type poly(3-alkynylthiophene-2,5-diyl) HH-P3(Ctriple bond; length of mdashCR)Th has been shown to exhibit a strong tendency to self-assemble. The UV–vis spectrum of HH-P3(Ctriple bond; length of mdashCDec)Th (Dec = decyl) in 1,2-dichlorobenzene at 131 °C showed a peak at λmax = 520 nm, which shifted to λmax = 553 nm at 25 °C, with a shoulder peak at 608 nm. However, the UV–vis spectrum of an HH-P3(Ctriple bond; length of mdashCDec)Th film showed a more pronounced shift in its UV–vis absorption peak to a longer wavelength. These phenomena are the characteristics of the self-assembly of the polymer molecule. The HH-P3(Ctriple bond; length of mdashCDec)Th film had a large third-order nonlinear optical susceptibility χ(3) of 3.6 × 10-11 esu.

DOI： 10.1016/j.synthmet.2007.04.002

Language：English   Publishing type：Research paper (scientific journal)  

New quasi-one-dimensional bromo-bridged PdII–PdIV
mixed-valence complexes with long chain alkylsufonates
[Pd(en)2][PdBr2(en)](CnH2nþ1SO3)4-2H2O (en = ethylenediamine, n = 7, 8, 9, and 10) were synthesized. With increasing alkyl-chain length (n) of the counter anions, the PdII ... PdIV distances decreased, indicating that the oxidation states of the Pd atoms are close to the PdIII state.

DOI： 10.1246/bcsj.80.189

Language：English   Publishing type：Research paper (scientific journal)  

This communication describes versatile vapochromic
behavior that is accompanied by a phase change between
charge-polarization (CP) and charge-density-wave (CDW)
states with increasing and decreasing temperature in [{NH3-
(CH2)5NH3}2][Pt2(pop)4I]4H2O (pop = P2H2O5
2) (1).

DOI： 10.1246/bcsj.79.1404

Language：English   Publishing type：Research paper (scientific journal)  

Sr2TMO3 (TM = Ni,Co) compounds with 1D TM-O chains have been successfully synthesized in the form of single-crystalline thin films using a combinatorial approach. The crystal structure is examined using X-ray diffraction and high-resolution TEM (see figure). Polarized absorption spectroscopy and third-harmonic generation spectroscopy reveal a 1D electronic structure and sizable nonlinear optical susceptibility, respectively, for Sr2NiO3.

DOI： 10.1002/adma.200501759

Language：English   Publishing type：Research paper (scientific journal)  

We synthesized a novel iodo-bridged linear chain platinum compound, having the quasi-twodimensional
charge-density-wave (CDW) ground state and the smallest band gap. In this compound, we discovered an anomalous valence state in the boundary region at which the CDW phase alternates in the crystal by means of ESR, X-ray diffuse scattering, STM, and electrical resistivity. This anomalous state can be explained by the fast fluctuation between PtIV-I...PtII and PtII...I-PtIV in the double well potential. This is the first observation of the dynamical fluctuation of the CDW phase among the quasi one-dimensional halogen-bridged complexes.

DOI： 10.1021/ja060193b

Language：English   Publishing type：Research paper (scientific journal)  

We report a splitting and a shift of exciton absorptions in semiconducting single-walled carbon
nanotubes (SWNTs) by resonant and off-resonant excitation using a fs laser pulse, respectively. This is
the first unambiguous observation of the optical Stark effect of excitons in SWNTs, which is responsible
for their high optical-switching performance. By scrutinizing transient absorption spectra from the midto
near-infrared region (0.1– 0.8 eV), the ultrafast recovery of real carrier excitations characteristic of
bundled structures was attributed to the energy- and charge-transfer processes to metallic SWNTs.

DOI： 10.1143/JPSJ.75.043709

Language：English   Publishing type：Research paper (scientific journal)  

Ultrafast photoinduced phase transition in a spin-Peierls (SP) system of K-tetracyanoquinodimethane
(K-TCNQ) was studied by femtosecond (fs) reflection spectroscopy. Photocarriers destabilize the SP
phase, resulting in a decrease in molecular dimerization within 400 fs. Such a melting of the SP phase
drives three kinds of coherent oscillations. By comparing the oscillations with the Raman bands activated
by the dimerization, we show that the oscillation of 20 cm1 is due to an LO phonon, and it plays an
important role for the stabilization of the SP phase.

DOI： 10.1103/PhysRevLett.96.037405

Language：English   Publishing type：Research paper (scientific journal)  

A pressure-induced neutral-to-ionic (N–I) transition in tetrathiafulvalene-p-chroranil was studied by
infrared vibration spectra. With increasing pressure, two CO stretching bands probing coexisting N and I
states merge due to rapid valence fluctuations. From the spectral analyses with the exchange-narrowing
model, we derive the pressure dependence of the N–I exchange rate related to the N–I domain-wall
motions, which explains the anomalous increase in conductivity under pressure. We also demonstrate a
para- to ferro-electric transition at 1.5 GPa as well as the N–I transition at 0.95 GPa.

DOI： 10.1143/JPSJ.74.2925

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/anie.200502216

Language：English   Publishing type：Research paper (scientific journal)  

We measured third-order nonlinear susceptibility (􀀂(3)) spectra in semiconducting single-walled carbon nanotubes (SWNTs) by the 􀀂-scan method. |Im􀀂(3)| is remarkably
enhanced under resonant excitation to the lowest interband transition, reaching 4.2 􀀂 10􀀂6 esu.
A comparison of the transient absorption changes evaluated by degenerate and nondegenerate pump-probe measurements suggests that the resonant enhancement of |Im􀀂(3)| is dominated by a coherent process rather than by incoherent one such as saturation of absorption.

DOI： 10.1088/1742-6596/21/1/029

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

We have investigated the third-order optical nonlinearity of poly3-hexylthiophenes with various
head-to-tail coupling ratios r, using the third-harmonic generation method.

DOI： 10.1063/1.2051795

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

We have investigated the linear and third-order nonlinear optical properties in a charge-transfer (CT) type conjugated copolymer, PThQx, which is composed of an electron-donating molecule, thiophene (Th), and electron-accepting one, quinoxaline (Qx), by using the linear absorption, two-photon absorption (TPA), and third-harmonic generation (THG) spectroscopies. In comparison with a homopolymer, polythiophene, the absorption coefficient α of PThQx is significantly reduced, while its third-order nonlinear susceptibility (χ(3)) is unchanged. This indicates that the figure of merit for the nonlinear optical materials, defined as χ(3)/α, is enhanced in PThQx. This enhancement comes from the CT character of the excited states in PThQx, in which a hole and an electron are created on different molecules.

DOI： 10.1016/j.synthmet.2005.07.147

Language：English   Publishing type：Research paper (scientific journal)  

The third-harmonic-generation (THG) spectrum was measured for a NiBr-chain compound, which is a
one-dimensional Mott insulator, in a reflection configuration. A sharp peak and a shoulder structure in the
THG spectrum are attributed to three-photon resonance to an exciton and a continuum, respectively. The
band-edge energy, the exciton binding energy, and the spectral weights for the exciton and the continuum
were determined from comparative studies of linear absorption, THG, and electroreflectance spectra. The
excitonic effect is more pronounced in the NiCl chain than in the NiBr chain.

DOI： 10.1103/PhysRevLett.95.087401

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/anie.200500091

Language：English   Publishing type：Research paper (scientific journal)  

We measured third-order nonlinear susceptibility spectra in semiconducting single-walled carbon
nanotubes (SWNTs) by the Z-scan method. Im chi^(3) is remarkably enhanced under resonant excitation to
the lowest interband transition, reaching 4×10^-6 esu and 1×10^-7 esu in SWNTs grown by the laser
ablation and HiPco methods, respectively. A comparison of the transient absorption changes evaluated by
degenerate and nondegenerate pump-probe measurements suggests that the resonant enhancement of
Im chi(3) is dominated by a coherent process rather than by saturation of absorption.

DOI： 10.1103/PhysRevLett.94.047404

Language：English   Publishing type：Research paper (scientific journal)  

Photoinduced transitions from ionic sId to neutral sNd and neutral sNd to ionic sId phases in an organic charge
transfer (CT) complex, tetrathiafulvalene-p-chloranil (TTF-CA), were investigated by femtosecond pumpprobe
reflection spectroscopy. Transient reflectivity changes of the intramolecular transition band of TTF
sensitive to the degree of CT between a donor molecule of TTF and an acceptor molecule of CA are measured
as a function of excitation energy, excitation density, and temperature. By adopting the multilayer model for the
analysis of the obtained transient reflectivity spectra, we have derived the time characteristics of amounts and
spatial distributions of photoinduced N sId states in the I sNd phase. The results reveal that the I to N sINd
transition induced by the resonant excitation of the CT band at 4 K is composed of three processes; (1)
formation of a confined one-dimensional (1D) N domain, that is, a sequence of D0A0 pairs, just after the
photoexcitation, (2) multiplication of the 1D N domains to the semimacroscopic N states up to 20 ps within the
absorption depth of the excitation light, and (3) proceeding of the IN transition along the direction normal to
the sample surface. At 77 K near the NI transition temperature sTc=81 Kd, the size of the 1D N domain
initially produced is enlarged and its multiplication process is strongly enhanced. When the excitation energy
is increased, the initial photoproduct is changed from the confined 1D N domain to the positively and negatively
charged N states. The spatial size of the latter is considerably larger than that of the former, indicating
that the introduction of charge carriers makes the neighboring I state strongly unstable. The dynamics of the
photoinduced N to I sNId transition has also been investigated. The 1D I domains are initially produced by
lights, however, they decay within 20 ps even if the density of the I domains is increased. The results demonstrate
that there is a cle

DOI： 10.1103/PhysRevB.70.165202

Language：English   Publishing type：Research paper (scientific journal)  

We report the reflectivity and the resistivity measurement of Ca2-xNaxCuO2Cl2 (CNCOC), which has a
single-CuO2-plane lattice with no orthorhombic distortion. The doping dependence of the in-plane optical
conductivity spectra for CNCOC is qualitatively the same to those of other cuprates, but a slight difference
between CNCOC and LSCO, i.e., the absence of the 1.5 eV peak in CNCOC, can be attributed to the smaller
charge-stripe instability in CNCOC. The temperature dependence of the optical conductivity spectra of CNCOC
has been analyzed both by the two-component model (Drude1Lorentzian) and by the one-component
model (extended-Drude analysis). The latter analysis gives a universal trend of the scattering rate Gsvd with
doping. It was also found that Gsvd shows a saturation behavior at high frequencies, whose origin is the same
as that of resistivity saturation at high temperatures.

DOI： 10.1103/PhysRevB.70.134501

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevB.70.125117

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

We have studied third-order nonlinear optical (NLO) properties of charge-transfer- (CT) type conjugated
copolymer composed of an electron-donating molecule, thiophene, and electron-accepting one, quinoxaline,
using the electroabsorption, two-photon absorption, and third-harmonic generation spectroscopies. The analyses
of the obtained nonlinear optical spectra reveal that the CT character of the excited states leads to small
oscillator strength of linear absorption but large third-order nonlinear susceptibility, resulting in the strong
enhancement of figure of merit for NLO devices.

DOI： 10.1103/PhysRevB.70.115205

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1103/PhysRevB.70.085101

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevB.70.035204

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/anie.200453905

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

This communication will describe the electron doping effect into NiIII complexes by CuII ions, [Ni1-xCux(chxn)2Br]Br2-x (x = 0.038 and 0.101) by using an electrochemical oxidation method. A drastic increase of electrical conductivity as well as a new absorption band around 0.5 eV in single crystal reflectance spectra was observed by doping CuII ions, indicating the electron doping was successfully made. An ESR result shows unpaired electrons locate in the dx2-y2 orbitals of CuII and have almost no interaction with those of other ions.

DOI： 10.1021/ic0349555

Language：English   Publishing type：Research paper (scientific journal)  

New molecular charge-transfer complexes of bis(ethylenedithio)tetrathiafulvalene (ET), (ET)Cu2Br4 (1), (ET)2Cu6Br10 (2), (ET)2[Cu4Br6ET] (3), (ET)2Cu2Br4 (4), (ET)2Cu3Br7(H2O) (5), and (ET)2Cu6Br10(H2O)2 (6), have been synthesized by diffusing reaction of ET and CuIIBr2. Their crystal structures and physical properties have been investigated. X-ray analyses revealed that ET molecules coordinated to the copper ions with the sulfur atoms of the ethylenedithio groups in all compounds. The Cu-S distances are found in the range 2.268(5)-2.417(8) Å, being close to the typical CuI-S coordination bond distances. Strong d- interactions between d-electrons of the copper ions and -electrons of the ET molecules can be expected through the Cu-S coordination bonds. ET molecules behave as trans-bidentate ligands bonding to two different copper ions in 1 and 3, as cis-bidentate ligands in 2, 5, and 6, and as monodentate ligands in 4. In the crystal structure of 3, there are two types of ET molecules in the crystal structure, where the first type is a trans-bidentate ligand and the second forms a stacking structure by itself. Compounds 1, 2, 4, and 6 show semiconducting behavior down to low temperature (RT = 1.6 × 10-2 S cm-1 and Ea = 122 meV for 1, RT = 2.1 S cm-1 and Ea = 21 meV for 2, RT = 5.4 × 10-4 S cm-1 and Ea = 239 meV for 4, and RT = 5.1 × 10-2 S cm-1 and Ea = 207 meV for 6). On the other hand, in 3, a metal-like region is observed along the b-axis and c-axis, due to the contribution of stacked ET molecules, and a metal-semiconductor transition occurs at 280 and 270 K, respectively. Also, 5 exhibits metallic conductivity in the temperature ranges 240-300 and 200-300 K along the b-axis and c-axis, respectively, despite the oxidation state of ET with 2+.

DOI： 10.1021/ic0344362

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

We have measured third-order nonlinear susceptibility (χ(3)) spectra of the two-dimensional (2D) cuprates La2CuO4 and Nd2CuO4 by third-harmonic generation. The |χ(3)| spectra exhibit broad peaks with maximum values of 0.6×10-10 esu in La2CuO4 and 2×10-10 esu in Nd2CuO4. These peaks are attributable to three-photon resonance to the charge transfer (CT) excited state. The χ(3) phase spectrum of Nd2CuO4 has revealed that the two-photon resonance to the even CT state are hidden on the high-energy side of the χ(3) peak. The difference in χ(3) values between the 2D and 1D cuprates is discussed by considering differences in spin-charge coupling and in charge configurations between the 2D and 1D cases.

DOI： 10.1103/PhysRevB.68.075101

Language：English   Publishing type：Research paper (scientific journal)  

We demonstrate the ultrafast photoinduced Mott transition from a charge transfer insulator to a
metal in a halogen-bridged Ni-chain compound by pump-probe reflection spectroscopy. Upon the
irradiation of a 130-femtosecond laser pulse, the spectral weight of the gap transition is transferred to
the inner-gap region. When the photoexcitation density exceeds 0:1=Ni site, the Drude-like highreflection
band appears in the infrared region, signaling the formation of a metallic state. The
photogeneration of the metallic state and the subsequent recovery to the original gapped state occur
within a few picoseconds.

DOI： 10.1103/PhysRevLett.91.057401

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0379-6779(02)00817-2

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0379-6779(02)00789-0

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0379-6779(02)00567-2

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/s0379-6779(02)00595-7

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0379-6779(02)00579-9

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

A new -conjugated charge-transfer-type copolymer of electron-donating thiophene and electron-accepting quinoxaline was prepared by organometallic polycondensation. The polymer was soluble in organic solvents such as tetrahydrofuran, and showed a UV-vis peak at long wavelengths of 598 nm in chloroform and 629 nm in the film. Its film exhibited a (3) peak in the resonance region with a (3) value comparable to that of regioregular head-to-tail poly(3-hexylthiophene-2,5-diyl).

DOI： 10.1002/marc.200390067

Language：English   Publishing type：Research paper (scientific journal)  

A new type of complex consisting of double liner-chain
structure {[Pt(en)2][PtCl2(en)2]g3(CuCl4)412H2O was synthesized. High concentration (ca. 200 times larger than the literature) of neutral soliton (PtIII component) formation was found. This unprecedented soliton formation mechanism will be discussed.

DOI： 10.1246/cl.2003.278

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

Electroreflectance (ER) spectra are measured on the mixed-stack charge transfer (CT) complexes, tetrathiafulvalane (TTF)-2-bromo-3,5,6-trichloro-p-benzoquinone (QBrCl3) and TTF-p-chloranil (QCl4), showing the neutral–ionic (N–I) phase transition. In the N phase of TTF-QBrCl3, we observe a large ER signal, which originates from the electric field-induced I domains in the N stacks. In contrast, no ER signal is obtained in the N phase of TTF-QCl4. The difference of the ER signal intensity between the two compounds is discussed by taking account of the difference in the degree of the valence instability.

DOI： 10.1016/S0379-6779(02)00357-0

Language：English   Publishing type：Research paper (scientific journal)  

In iodine-bridged binuclear Pt compounds, R4Pt2pop4InH2O and R02Pt2pop4InH2O (pop P2O5H2 2 ), electronic structures on the PtPtI chains have been controlled between a diamagnetic chargedensity-
wave (CDW) state and a paramagnetic charge-polarization (CP) state by modification of the
counterions (R, R0) located between chains. In the R C2H52NH2 compound, a pressure-induced CP
to CDW transition with a drastic color change is identified. This transition is accompanied by a large
hysteresis loop within which photoinduced transition between CDWand CP can be driven by selecting
the excitation photon energy.

DOI： 10.1103/PhysRevLett.90.046401

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1080/1058726021000045315

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1080/01411590290033921

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1006/jssc.2002.9689

Language：English   Publishing type：Research paper (scientific journal)  

This communication describes the syntheses of the quasi-onedimensional
mixed-halogen-bridged NiIII complexes with strong
electron correlation [Ni(chxn)2Cl1-xBrx](NO3)2 and the tuning of the
spin density wave strengths of these compounds. If the Cl 3p and
Br 4p make one band in the compounds, we should observe a
single peak in the electronic spectra. As a result, we should observe
the single peak from 1.45 to 2.00 eV depending on the mixing
ratios of Cl and Br ions. Therefore, the Cl 3p and Br 4p make one
band. Then, we have succeeded in tuning the spin density wave
strengths of the NiIII complexes with the strong electron correlation
by mixing the bridging halogen ions successively.

DOI： 10.1021/ic025654i

Language：English   Publishing type：Research paper (scientific journal)  

We report results of the angle-resolved photoemission experiments on a quasi-one-dimensional halogenbridged
complex [Ni(chxn)2Br]Br2 (chxn = 1R, 2R-cyclohexanediamine), which is a one-dimensional
Heisenberg spin chain with S = 1=2 and J 3600 K. The expected two dispersions, originated with
spin{charge separations as have been observed in other quasi-one-dimensional electron systems like
Sr2CuO3, are not clearly observed in this compound. Instead, only one \band" having about 0.5 eV
energy dispersion is found in the half of the Brillouin zone.

DOI： 10.1142/S0218625X02003354

Language：English   Publishing type：Research paper (scientific journal)  

A series of single crystals of quasi-one-dimensional Ni-Pd mixed-metal MX-chain compounds, Ni 1-x Pd x (chxn) 2 Br 3 , and mixed-halogen MX-chain compounds, Ni(chxn) 2 Cl y Br 1-y (NO 3 ) 2 have been obtained by electrochemical oxidation methods. In order to investigate the electronic states of these compounds, the optical conductivity spectra have been measured. These results indicate that the electronic states of the Ni compounds can be controlled by forming the mixed-metal or mixed-halogen systems.

DOI： 10.1080/713738467

Language：English   Publishing type：Research paper (scientific journal)  

The crystal structures of (C n H 2n+1 ) 2 NH 2 4 [Pt 2 (pop) 4 I] (pop=O(PO 2 H) 2 2- , n=2-6) have been determined. Judging from the results of the X-ray structural analyses and Raman spectra, 1-D electronic structures of these compounds are consider to be Pt 2+ -Pt 3+ -X Pt 2+ -Pt 3+ -X charge-polarized states.

DOI： 10.1080/10587250210759

Language：English   Publishing type：Research paper (scientific journal)  

We report on the results of angle-resolved photoemission experiments on a quasi-one-dimensional (1D) MX-chain compound [Ni(chxn)2Br]Br2, which shows a gigantic nonlinear optical effect. A “band" having about 500 meV energy dispersion is found in the first half of the Brillouin zone, but disappears at kb/π∼1/2. These spectral features are well reproduced by the d-p chain model with a small charge-transfer energy Δ compared with that of 1D Cu-O compounds. We propose that this smaller Δ is the origin of the absence of clear spin-charge separation in the photoemission spectra and the strong nonlinear optical effect.

DOI： 10.1103/PhysRevLett.88.247601

Language：English   Publishing type：Research paper (scientific journal)  

We have succeeded in synthesizing the NiIII complexes doped by CoIII ions, [Ni1-xCox(chxn)2Br]Br2 (x = 0, 0.043, 0.093, and 0.118) by using an electrochemical oxidation method. The single-crystal reflectance spectrum of x = 0.118 shows an intense CT band about 0.5 eV, which is lower than that of [Ni(chxn)2Br]Br2 (1.3 eV). The single-crystal electrical conductivities at room temperature of these compounds increase with increase of the amounts of doping of CoIII ions. In the ESR spectra, peak-to-peak line widths Hpp at room temperature change about 600 G in [Ni(chxn)2Br]Br2 to 200 G in x = 0.118. Such a large x dependence of Hpp seems to be ascribed to the increasing contribution from the increasing Curie spins which have smaller line width. Therefore, we have tuned the electronic structures of quasi-one-dimensional bromo-bridged NiIII complexes with strong electron correlations by doping of CoIII ions.

DOI： 10.1021/ic011326r

Language：English   Publishing type：Research paper (scientific journal)  

Ultrafast optical switching from an ionic ( I) to a neutral ( N) state in TTF-CA was observed in femtosecond reflection spectroscopy. Charge transfer excitation in the I phase produces N donor ( D0) acceptor ( A0) strings within 2 ps. These initial N states decay with a lifetime of 300 ps at 4 K, but rather multiply leading to macroscopic I-N conversion within 20 ps at 77 K just below the N-I transition temperature TNI. Near TNI, we also found the evidence for the coherent motion of the macroscopic N-I domain boundary with a period of 85 ps.

DOI： 10.1103/PhysRevLett.88.057402

Language：English   Publishing type：Research paper (scientific journal)  

Spectra of the third-order nonlinear susceptibility χ(3) have been investigated for one-dimensional Mott insulators, Sr2CuO3 and Ca2CuO3, by applying the third-harmonic generation (THG) spectroscopy on their single-crystalline thin films. The three-photon resonance to the lowest charge-transfer (CT) state with odd parity strongly enhances χ(3), which is of the order of 10-9 esu. The two-photon resonant structure unravels the even-CT state, located close to the odd-CT state. Two types of χ(3) spectra obtained from THG and the electroreflectance measurements are explained based on the concept of spin-charge separation.

DOI： 10.1103/PhysRevLett.87.177401

Language：English   Publishing type：Research paper (scientific journal)  

The one-dimensional Cu–O chains responsible for the large optical nonlinearity in Sr2CuO3 (SCO) and Ca2CuO3 (CCO) are aligned in one direction in films grown on LaSrAlO4 (LSAO) (1 0 0) substrates by using pulsed laser deposition. The CCO films deposited directly on lattice matched LSAO substrates have a single orientation with high crystallinity, while the SCO films include small portions of misoriented domains. Using a simple model of lattice mismatch, we developed a Sr2TiO4 buffer layer in order to grow orientation-controlled SCO films with both high crystallinity and a sharp optical absorption edge. This technique will be a key to fabricating ultrafast all-optical switches with a waveguide structure.

DOI： 10.1063/1.1402161

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0379-6779(00)00996-6

Language：English   Publishing type：Research paper (scientific journal)  

Thin films of a helical polysilane with chiral substituents were fabricated using a Langmuir-Blodgett (LB) method. The polarized absorption and photoluminescence spectra show the high anisotropy for the LB films with the polymer backbone lying in-plane along the dipping direction. The anisotropy of the lowest exciton absorption band can be enhanced by annealing the LB films. With use of the oriented LB film, we have revealed the one-dimensional exciton structures characteristic of polysilanes with helical conformations by measurements of electroabsorption spectra, compared with those of polysilanes of other conformations such as trans-planar and alternating trans-gauche backbone structures. The large binding energies of the lowest exciton are generic in the one-dimensional regular polysilanes, irrespective of the conformations.

DOI： 10.1021/la0010774

Language：English   Publishing type：Research paper (scientific journal)  

New quasi-one-dimensional halogen-bridged platinum binuclear mixed-valence compounds, A4[Pt2(pop)4I]·nH2O (A=alkaline metal and NH4, and; n=0, 2 and 4) have been synthesized. The Li, Na and K compounds take structures -Pt2.5+-Pt2.5+-X-Pt2.5+-Pt2.5+-X- (a). On the other hand, the Cs and Rb compounds take structures Pt2+-Pt2+X-Pt3+-Pt3+-X (b). Interestingly, the NH4 compound takes a phase transition between (a) and (b) around 200K.

DOI： 10.1080/10587250008038258

Language：English   Publishing type：Research paper (scientific journal)  

We have synthesized helical polysilanes on which the pendant groups are partly substituted by dye molecules. The introduction of a few percent of dye molecules into the substituents enhances the luminescent efficiency of the visible region, by behaving as luminescence centers. We have demonstrated that the excitation energy is transferred efficiently by free excitons on the Si backbones to reach the luminescence centers, where energy transfer occurs from the exciton to the dye molecule, and as a result sensitized luminescence occurs. The exciton transfer is found to occur over 50–100 monomer units on the polysilane backbone. This approach will open the way to fabricating a wavelength-tunable luminous device by utilizing the exciton transport on Si chains.

DOI： 10.1063/1.1318395

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/35016036

Language：English   Publishing type：Research paper (scientific journal)  

To study nature of photo-excited states in one-dimensional (1D) strongly correlated electron systems, we have synthesized the halogen(X)-bridged Ni compounds, [Ni(chxn)2X]Y2 (X=Cl or Br; Y=Cl, Br, NO3 or ClO4; (chxn)=cyclohexanediamine), which have 1D Ni–X chains. These Ni compounds are charge-transfer (CT) insulators, showing strong CT transitions from the occupied halogen p band to the Ni d upper Hubbard band. The CT transition energies can be systematically controlled from 1.3 to 2.0 eV by the choice of the bridging-halogen ions X and the counter ions Y. From the excitation profiles of the photoconductivities, excitonic effects in the Ni-X chains have been found to depend strongly on the degree of pd hybridization.

DOI： 10.1016/S0022-2313(99)00262-8

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

We have investigated the electroabsorption spectrum for a thin film of the silicon oligomer Si10(CH3)22, a finite-chain analog of quasi-one-dimensional semiconductor polysilanes. The obtained spectrum can be well reproduced by a four-level model in which a one-photon-forbidden state is located between two one-photon-allowed states. By comparison with the spectra of polysilanes, it was found that the transition dipole moment between the excited states decreases significantly with a decrease of chain length. This can be ascribed to the confinement of the excited states.

DOI： 10.1103/PhysRevB.54.R14254

Language：English   Publishing type：Research paper (scientific journal)  

A method of phase retrieval from the experimental modulus ux (3)u spectra of third-order nonlinear optical susceptibility
is presented on the basis of the maximum-entropy model. This method enables one to derive the
real and the imaginary parts of x (3) without using the nonlinear Kramers–Kronig calculation, which is usually
hazardous in nonlinear optical spectroscopy because of the limited range of measurements. Theoretical and
experimental modulus spectra of polysilane are analyzed. The results from the experimental modulus are
compared with the Kramers–Kronig calculations as well as with the measured phase values. It is also shown
how the method can be optimized to reduce the distortions that result from noise in the calculated spectra.

DOI： 10.1364/JOSAB.13.002106

Language：English   Publishing type：Research paper (scientific journal)  

One-dimensional (1D) exciton states have been studied by nonlinear optical spectroscopy on organosilicon polymer polysilanes (PS's). From systematic variation of the linear and nonlinear optical spectra upon changing the backbone conformation, the following two characteristic exciton parameters have been evaluated; the ratio |χ(3)|/α of the modulus of third-order nonlinear optical susceptibility |χ(3)| to the absorption coefficient α; and the energy difference ΔE12 between the lowest and second lowest exciton energies E1 and E2, which are theoretically related, respectively, to the Bohr radius and to the binding energy of excitons. It was found that |χ(3)|/α increases, whereas ΔE12 remains almost unchanged, with increasing valence and conduction-band widths. These features cannot be accounted for either by the Wannier- or Frenkel-type exciton model. From analysis by a unified 1D exciton model, it has been concluded that the 1D excitons in PS's represent a unique system having an intermediate character in between the Frenkel- and Wannier-exciton regimes, where the on-site Coulomb (or exchange) interactions play a crucial role in determining the characteristic exciton structures as observed.

DOI： 10.1103/PhysRevB.54.11365

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

Optical absorption spectra have been measured for finite-chain analogs of linear polysilane, silicon oligomers CH3[Si(CH3)2]nCH3, with controlled chain length n(=2 to 16). The intense lowest electronic absorption peak and its higher-lying side bands, which correspond to the one-dimensional exciton series in the infinite chain, shift to higher energy with decrease of the chain length because of the confinement of the excited states. The oscillator strength of the main absorption peak increases with the chain length, while the linewidth of the main peak drastically decreases, especially in the region n=2 to 6. These finite size effects of the electronic (excitonic) absorption are argued in terms of spatial extension of the excited states, motional narrowing and electron correlation effect.

DOI： 10.1143/JPSJ.65.1578

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

The size dependence of the optical spectra of the exciton-phonon coupled system is studied theoretically. As the sample size N increases, the optical spectrum generally crosses over from Gaussian to Lorentzian with motional narrowing due to the increased itineracy of the exciton. It is found that this crossover depends strongly on the ratios W/D and W/(ħωD) (W is the exciton bandwidth, D the site energy fluctuation, and ωD the Debye frequency). Even nonmonotonic behavior is found in the numerical study.

DOI： 10.1103/PhysRevB.53.12574

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

Luminescence spectra and their variation with temperature have been investigated for solid films of poly(methylphenylsilane) and its branched analogs. Introduction of branching points to the polymers enhances the broad luminescence band in the visible region while suppressing the sharp UV luminescence band due to the resonant recombination of the exciton. The intensity of the visible luminescence is observed to keep on increasing with decreasing temperature in contrast with the nearly temperature-independent intensity of the resonant luminescence. The behavior is interpreted in terms of phonon-assisted tunneling between luminescence centers and nonradiative ones.

DOI： 10.1063/1.359962

Language：English   Publishing type：Research paper (scientific journal)  

The exciton spectra have been investigated on thin films of β-carotene and related polyenes, having all-trans conformation. By using electro-modulation technique, it has been found that there is a one-photon forbidden n1Ag exciton in β-carotene film at about 4.0 eV above the lowest allowed 11Bu exciton at 2.25 eV at 77K.

Language：English   Publishing type：Research paper (scientific journal)  

The third-order nonlinear optical (NLO) susceptibility χ(3)(-3ω;ω,ω,ω) have been measured on spin-coated films of three kinds of polysilanes (PS's) with various backbone conformations, in a wide range of fundamental wavelength, by means of third-harmonic generation (THG) measurement. The experimental results show that their quasi-one-dimensional (Q1D) exciton level structures and their optical nonlinearity systematically change, with their backbone conformation changes. As compared with the theoretical calculation by 1D exciton model, the experimental feature indicates that the on-site electron correlation takes important roles in Q1D exciton states of PS's.

DOI： 10.1109/STSM.1994.835738

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

Optical properties of the branched and network silicon polymers have been studied. By introduction of the branching points onto the polysilanes, the absorption spectrum, which is characterized by a sharp excitonic peak, changes gradually into the amorphous-like one, while the uv luminescence disappears immediately with branching and the broad visible luminescence shows up. The network polymers, in which all backbones atoms are coordinated by three other backbone atoms in the limit of branching, show amorphous-like absorption spectra. by Ge-substitution for Si atoms in the backbone of network polymers, and absorption edge as well as the luminescence peak shift to the lower energy side by c.a. 0.5eV.

DOI： 10.7567/JJAPS.34S1.104

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

The third-order nonlinear-susceptibility χ(3)(-2ω;ω,ω,0) spectrum has been investigated for thin films of linear-Si-chain compounds, poly(dihexylsilane), by measurements of electric-field-induced second-harmonic generation (EFISHG). In the χ(3) spectrum for EFISHG, two-photon resonance structures to the first and second levels of one-dimensional excitons were observed. The observed χ(3) spectrum can be accounted for by considering multiple optical processes in the one-dimensional excitonic series characteristic of the Si-chain system.

DOI： 10.1103/PhysRevB.50.7786

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

Optical properties of silicon- and germanium-based network copolymers, [Si(C6H13)]1-x[Ge(C6H13)]x, have been investigated for various Si/Ge compositions (x). The backbone Si/Ge atoms are coordinated by the three other Si/Ge backbone atoms in the polymers. These Si/Ge copolymers show the absorption spectra which are typical of amorphous semiconductors. Their color continuously traverses the visible range with x, which is due to the change of the band gap (Tauc gap) energy as well as to the presence of localized subgap states. The Si/Ge copolymer shows a broad band of luminescence in the visible region. The luminescence band maximum was observed to shift by 0.5 eV with change of the Si/Ge ratio.

DOI： 10.1063/1.112051

Language：English   Publishing type：Research paper (scientific journal)  

Optical properties of the branched and network silicon polymers have been studied. By introduction of the branching points onto the polysilanes, the absorption spectrum, which is characterized by a sharp excitonic peak, changes gradually into the amorphous-like one, while the uv luminescence disappears immediately with branching and the broad visible luminescence shows up. The network polymers, in which all backbones atoms are coordinated by three other backbone atoms in the limit of branching, show amorphous-like absorption spectra. By Ge-substitution for Si atoms in the backbone of network polymers, an absorption edge as well as the luminescence peak shift to the lower energy side by c.a. 0.5eV.

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Single crystal x-ray crystallographic analysis of tert-butyloctasilacubane showed that a new polymorphic form ( form) exists with a slightly modified shape of the Si cage as compared with the previously reported form ( form) [K. Furukawa, M. Fujino, and N. Matsumoto, Appl. Phys. Lett. 60, 2744 (1991)]. Spectroscopic investigations of the single crystal indicate that the electronic band gap and luminescence band position differ by ~0.4 eV between the polymorphs, signaling the sensitivity of the electronic structure to the distortion of the octasilacubane framework. Applied Physics Letters is copyrighted by The American Institute of Physics.

DOI： 10.1063/1.111556

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevLett.70.3724

Language：English   Publishing type：Research paper (scientific journal)  

We have measured a spectrum of third-order nonlinear optical susceptibility |x (3)(-3;,,)| of -conjugated polysilane, poly(di-n-hexylsilane) (PDHS), by means of third-harmonic generation (THG) measurement, in the fundamental photon energy region from 0.56 eV to 2.15 eV. The obtained | x (3)(3; , , )| spectrum exhibits three peaks. These peaks are interpreted as the multi-photon resonance enhancement to the one-dimensional exciton states. This exciton model can be applied also to the nonlinear optical response of other conjugated polymers.

DOI： 10.1080/10587259208046871

Language：English   Publishing type：Research paper (scientific journal)  

Third-order nonlinear-optical susceptibility spectra ‖χ(3)(-3ω;ω,ω,ω)‖ have been obtained for poly(dihexylsilane) (PDHS) and poly(dibutylsilane) (PDBS) films by third-harmonic generation (THG) measurements for a fundamental photon energy region from 1.90 to 2.15 eV, which covers the two-photon absorption (TPA) for PDHS but not for PDBS. The ‖χ(3)‖ spectrum for PDHS shows a prominent peak at about 2.08 eV with a maximum value of about 2.3×10-12 esu, while there is no enhancement effect in PDBS in the same fundamental photon energy region. These results provide direct evidence for the two-photon-resonant THG process in polysilanes due to the one-photon-forbidden 1Ag exciton detected by TPA and electroabsorption measurements.

DOI： 10.1103/PhysRevB.45.6317

Language：Japanese

Language：Japanese

Language：Japanese

種々の分光法の中でも電子状態について多くの情報が得られる変調分光法について、実験手法、実際の実験結果、解析手法について解説する。

Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

Event date： 2024.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：北海道大学　札幌キャンパス（北海道札幌市）   Country：Japan  

Event date： 2024.9

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Venue：北海道大学　札幌キャンパス（北海道札幌市）   Country：Japan  

Event date： 2024.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：北海道大学　札幌キャンパス（北海道札幌市）   Country：Japan  

Event date： 2024.3

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2024.3

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Venue：オンライン開催（Zoomミーティング）   Country：Japan  

Event date： 2024.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン開催（Zoomミーティング）   Country：Japan  

Event date： 2024.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン開催（Zoomミーティング）   Country：Japan  

Event date： 2024.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン開催（Zoomミーティング）   Country：Japan  

Event date： 2024.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン開催（Zoomミーティング）   Country：Japan  

Event date： 2024.3

Language：English   Presentation type：Oral presentation (general)  

Venue：Minneapolis, Minnesota, USA   Country：United States  

Event date： 2023.12

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2023.12

Language：English   Presentation type：Poster presentation  

Country：Japan  

Event date： 2023.9

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2023.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東北大学   Country：Japan  

Event date： 2023.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東北大学   Country：Japan  

Event date： 2023.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東北大学   Country：Japan  

Event date： 2023.9

Language：Japanese   Presentation type：Poster presentation  

Venue：東北大学   Country：Japan  

Event date： 2023.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東北大学   Country：Japan  

Event date： 2023.8

Language：Japanese   Presentation type：Poster presentation  

Venue：名古屋大学「坂田平田ホール」   Country：Japan  

Event date： 2023.8

Language：English   Presentation type：Poster presentation  

Venue：Hokkaido Univ.   Country：Japan  

Event date： 2023.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2023.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2023.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2023.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2023.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2023.3

Language：English   Presentation type：Oral presentation (general)  

Venue：Las Vegas, Nevada, USA   Country：United States  

Event date： 2023.3

Presentation type：Oral presentation (general)  

Event date： 2022.10

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：東北大学   Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue： 川内北キャンパス＋オンライン開催   Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京工業大学   Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Poster presentation  

Venue：東京工業大学   Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Poster presentation  

Venue：東京工業大学   Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Poster presentation  

Venue：東京工業大学   Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京工業大学   Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京工業大学   Country：Japan  

Event date： 2022.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：青山学院大学＆オンライン   Country：Japan  

Event date： 2022.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2022.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2022.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2022.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2022.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2022.3

Language：English   Presentation type：Oral presentation (general)  

Event date： 2021.12

Language：English   Presentation type：Oral presentation (general)  

Venue：Nagoya University, Nagoya, Aichin   Country：Japan  

Event date： 2021.10

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：アクリエひめじ（兵庫県姫路市）   Country：Japan  

Event date： 2021.9

Language：Japanese   Presentation type：Poster presentation  

Venue：オンライン   Country：Japan  

Event date： 2021.9

Language：Japanese   Presentation type：Poster presentation  

Venue：オンライン   Country：Japan  

Event date： 2021.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2021.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2021.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2021.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2021.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2021.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2021.7

Language：English   Presentation type：Oral presentation (general)  

Venue：South Lake Hotel, Changchun, China (In-person/Online hybrid)   Country：China  

Event date： 2021.3

Language：English   Presentation type：Oral presentation (general)  

Venue：オンライン開催   Country：United States  

Event date： 2021.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン開催   Country：Japan  

Event date： 2021.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン開催   Country：Japan  

Event date： 2021.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン開催   Country：Japan  

Event date： 2020.9

Language：English   Presentation type：Oral presentation (general)  

Venue：オンライン開催   Country：Japan  

Event date： 2020.9

Language：English   Presentation type：Poster presentation  

Venue：オンライン開催   Country：Japan  

Event date： 2020.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン開催   Country：Japan  

Event date： 2020.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン開催   Country：Japan  

Event date： 2020.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン開催   Country：Japan  

Event date： 2020.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン開催   Country：Japan  

Event date： 2020.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋大学 東山キャンパス（名古屋市）（新型コロナウイルス感染症関係の対応により現地開催中止）   Country：Japan  

Event date： 2020.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋大学 東山キャンパス（名古屋市）（新型コロナウイルス感染症関係の対応により現地開催中止）   Country：Japan  

Event date： 2020.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋大学 東山キャンパス（名古屋市）（新型コロナウイルス感染症関係の対応により現地開催中止）   Country：Japan  

Event date： 2020.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋大学 東山キャンパス（名古屋市）（新型コロナウイルス感染症関係の対応により現地開催中止）   Country：Japan  

Event date： 2020.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋大学 東山キャンパス（名古屋市）（新型コロナウイルス感染症関係の対応により現地開催中止）   Country：Japan  

Event date： 2020.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋大学 東山キャンパス（名古屋市）（新型コロナウイルス感染症関係の対応により現地開催中止）   Country：Japan  

Event date： 2020.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋大学 東山キャンパス（名古屋市）（新型コロナウイルス感染症関係の対応により現地開催中止）   Country：Japan  

Event date： 2020.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：上智大学 四谷キャンパス（東京都千代田区）（新型コロナウイルス感染症関係の対応により中止、発表は講演予稿集の発行を持って成立とする）   Country：Japan  

Event date： 2020.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：上智大学 四谷キャンパス（東京都千代田区）（新型コロナウイルス感染症関係の対応により中止、発表は講演予稿集の発行を持って成立とする）   Country：Japan  

Event date： 2020.3

Language：English   Presentation type：Oral presentation (general)  

Venue：Denver, CO, USA (Oral　12分, session W56.00013)　新型コロナウイルスのため開催中止   Country：United States  

Event date： 2020.3

Language：English   Presentation type：Oral presentation (general)  

Venue：Denver, CO, USA (Oral　12分, session, A57.00010)　コロナウイルスのため開催中止   Country：United States  

Event date： 2019.12

Language：English   Presentation type：Oral presentation (general)  

Venue：Boston, Massachusetts, USA   Country：United States  

Event date： 2019.10

Language：English   Presentation type：Oral presentation (general)  

Venue：広島国際会議場(広島県広島市)   Country：Japan  

Event date： 2019.10

Language：English   Presentation type：Oral presentation (general)  

Venue：広島国際会議場(広島県広島市)   Country：Japan  

Event date： 2019.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：北海道大学　札幌キャンパス（北海道札幌市）   Country：Japan  

Event date： 2019.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：岐阜大学（柳戸キャンパス）　(岐阜県岐阜市）   Country：Japan  

Event date： 2019.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：岐阜大学（柳戸キャンパス）　(岐阜県岐阜市）   Country：Japan  

Event date： 2019.9

Language：Japanese   Presentation type：Poster presentation  

Venue：岐阜大学（柳戸キャンパス）　(岐阜県岐阜市）   Country：Japan  

Event date： 2019.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：岐阜大学（柳戸キャンパス）　(岐阜県岐阜市）   Country：Japan  

Event date： 2019.9

Language：Japanese   Presentation type：Poster presentation  

Venue：岐阜大学（柳戸キャンパス）　(岐阜県岐阜市）   Country：Japan  

Event date： 2019.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：岐阜大学（柳戸キャンパス）　(岐阜県岐阜市）   Country：Japan  

Event date： 2019.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：岐阜大学（柳戸キャンパス）　(岐阜県岐阜市）   Country：Japan  

Event date： 2019.9

Language：Japanese   Presentation type：Poster presentation  

Venue：岐阜大学（柳戸キャンパス）　(岐阜県岐阜市）   Country：Japan  

Event date： 2019.9

Language：Japanese   Presentation type：Poster presentation  

Venue：岐阜大学（柳戸キャンパス）　(岐阜県岐阜市）   Country：Japan  

Event date： 2019.9

Language：Japanese   Presentation type：Poster presentation  

Venue：岐阜大学（柳戸キャンパス）　(岐阜県岐阜市）   Country：Japan  

Event date： 2019.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋大学　理学南館 坂田・平田ホール（愛知県名古屋市）   Country：Japan  

Event date： 2019.9

Language：English   Presentation type：Poster presentation  

Venue：名古屋大学　理学南館 坂田・平田ホール（愛知県名古屋市）   Country：Japan  

Event date： 2019.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学（伊都キャンパス）　(福岡県福岡市）   Country：Japan  

Event date： 2019.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学（伊都キャンパス）　(福岡県福岡市）   Country：Japan  

Event date： 2019.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学（伊都キャンパス）　(福岡県福岡市）   Country：Japan  

Event date： 2019.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学（伊都キャンパス）　(福岡県福岡市）   Country：Japan  

Event date： 2019.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学（伊都キャンパス）　(福岡県福岡市）   Country：Japan  

Event date： 2019.3

Language：English   Presentation type：Oral presentation (general)  

Venue：九州大学（伊都キャンパス）　(福岡県福岡市）   Country：Japan  

Event date： 2018.12

Language：English   Presentation type：Oral presentation (keynote)  

Venue：CSIR-National Physical Laboratory, New Delhi, India   Country：India  

Event date： 2018.10

Language：English   Presentation type：Poster presentation  

Venue：Toyota Physical and Chemical Research Institute, Hiroo INOKUCHI Hall, Nagakute, Aichi, Japan   Country：Japan  

Event date： 2018.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋国際会議場（愛知県名古屋市）   Country：Japan  

Event date： 2018.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋国際会議場（愛知県名古屋市）   Country：Japan  

Event date： 2018.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋国際会議場（愛知県名古屋市）   Country：Japan  

Event date： 2018.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：同志社大学　京田辺キャンパス　(京都府京田辺市）   Country：Japan  

Event date： 2018.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：同志社大学　京田辺キャンパス　(京都府京田辺市）   Country：Japan  

Event date： 2018.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：同志社大学　京田辺キャンパス　(京都府京田辺市）   Country：Japan  

Event date： 2018.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：同志社大学　京田辺キャンパス　(京都府京田辺市）   Country：Japan  

Event date： 2018.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：同志社大学　京田辺キャンパス　(京都府京田辺市）   Country：Japan  

Event date： 2018.9

Language：English   Presentation type：Poster presentation  

Venue：Nagaragawa Convention Center (長良川国際会議場), Gifu, Japan   Country：Japan  

Event date： 2018.9

Language：English   Presentation type：Poster presentation  

Venue：Nagaragawa Convention Center (長良川国際会議場), Gifu, Japan   Country：Japan  

Event date： 2018.7 - 2018.8

Language：English   Presentation type：Poster presentation  

Venue：Corum conference center, Montpellier, France   Country：France  

Event date： 2018.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京理科大学　野田キャンパス　(千葉県野田市）   Country：Japan  

Event date： 2018.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京理科大学　野田キャンパス　(千葉県野田市）   Country：Japan  

Event date： 2018.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京理科大学　野田キャンパス　(千葉県野田市）   Country：Japan  

Event date： 2018.3

Language：Japanese   Presentation type：Poster presentation  

Venue：東京理科大学　野田キャンパス　(千葉県野田市）   Country：Japan  

Event date： 2018.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京理科大学　野田キャンパス　(千葉県野田市）   Country：Japan  

Event date： 2018.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京理科大学　野田キャンパス　(千葉県野田市）   Country：Japan  

Event date： 2018.3

Language：English   Presentation type：Poster presentation  

Venue：東京大学　伊藤国際学術研究センター（東京都）   Country：Japan  

Event date： 2018.3

Language：English   Presentation type：Poster presentation  

Venue：東京大学　伊藤国際学術研究センター（東京都）   Country：Japan  

Event date： 2018.3

Language：English   Presentation type：Poster presentation  

Venue：東京大学　伊藤国際学術研究センター（東京都）   Country：Japan  

Event date： 2017.11

Language：English   Presentation type：Poster presentation  

Venue：Nagoya University, Chikusa, Nagoya   Country：Japan  

Event date： 2017.9 - 2017.10

Language：English   Presentation type：Poster presentation  

Venue：Nagoya University, Chikusa, Nagoya   Country：Japan  

Event date： 2017.9 - 2017.10

Language：English   Presentation type：Oral presentation (general)  

Venue：Nagoya University, Chikusa, Nagoya   Country：Japan  

Event date： 2017.9

Language：English   Presentation type：Oral presentation (general)  

Venue：Institute for Materials Research, Tohoku University, Sendai, Japan   Country：Japan  

Event date： 2017.9

Language：English   Presentation type：Oral presentation (general)  

Venue：Miyagi, Japan   Country：Japan  

Event date： 2017.9

Language：English   Presentation type：Poster presentation  

Venue：Miyagi Zao Royal Hotel, Miyagi, Japan   Country：Japan  

Event date： 2017.9

Language：English   Presentation type：Poster presentation  

Venue：Miyagi Zao Royal Hotel, Miyagi, Japan   Country：Japan  

Event date： 2017.9

Language：English   Presentation type：Poster presentation  

Venue：Miyagi Zao Royal Hotel, Miyagi, Japan   Country：Japan  

Event date： 2017.9

Language：Japanese   Presentation type：Poster presentation  

Venue：岩手大学　上田キャンパス（盛岡市）   Country：Japan  

Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：岩手大学　上田キャンパス（盛岡市）   Country：Japan  

Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：岩手大学　上田キャンパス（盛岡市）   Country：Japan  

Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：岩手大学　上田キャンパス（盛岡市）   Country：Japan  

Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：岩手大学　上田キャンパス（盛岡市）   Country：Japan  

Event date： 2017.9

Language：Japanese   Presentation type：Poster presentation  

Venue：岩手大学　上田キャンパス（盛岡市）   Country：Japan  

Event date： 2017.6

Language：English   Presentation type：Poster presentation  

Venue：Sendai International Center, Sendai, Japan   Country：Japan  

Event date： 2017.6

Language：English   Presentation type：Oral presentation (general)  

Venue：Sendai International Center, Sendai, Japan   Country：Japan  

Event date： 2017.6

Language：English   Presentation type：Oral presentation (general)  

Venue：Sendai International Center, Sendai, Japan   Country：Japan  

Event date： 2017.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：大阪大学　豊中キャンパス（豊中市）   Country：Japan  

Event date： 2017.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：金沢大学　角間キャンパス（金沢市）   Country：Japan  

Event date： 2017.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：金沢大学　角間キャンパス（金沢市）   Country：Japan  

Event date： 2017.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：大阪大学　豊中キャンパス（豊中市）   Country：Japan  

Event date： 2017.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：大阪大学　豊中キャンパス（豊中市）   Country：Japan  

Event date： 2017.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：大阪大学　豊中キャンパス（豊中市）   Country：Japan  

Event date： 2017.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：大阪大学　豊中キャンパス（豊中市）   Country：Japan  

Event date： 2017.3

Language：Japanese   Presentation type：Poster presentation  

Venue：大阪大学　豊中キャンパス（豊中市）   Country：Japan  

Event date： 2016.12

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：横浜市中区   Country：Japan  

Event date： 2016.10

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学筑紫キャンパス 筑紫ホール   Country：Japan  

Event date： 2016.10

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学筑紫キャンパス 筑紫ホール   Country：Japan  

Event date： 2016.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：金沢大学　角間キャンパス（金沢市）   Country：Japan  

Event date： 2016.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：金沢大学　角間キャンパス（金沢市）   Country：Japan  

Event date： 2016.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：金沢大学　角間キャンパス（金沢市）   Country：Japan  

Event date： 2016.9

Language：English   Presentation type：Oral presentation (general)  

Venue：福岡市   Country：Japan  

Event date： 2016.3

Language：English   Presentation type：Poster presentation  

Venue：同志社大学　京田辺キャンパス   Country：Japan  

Event date： 2016.3

Language：Japanese   Presentation type：Poster presentation  

Venue：東北学院大学　泉キャンパス　（仙台市）   Country：Japan  

Event date： 2016.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東北学院大学　泉キャンパス　(仙台市）   Country：Japan  

Event date： 2016.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東北学院大学　泉キャンパス　(仙台市）   Country：Japan  

Event date： 2016.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東北学院大学　泉キャンパス　(仙台市）   Country：Japan  

Event date： 2016.3

Language：English   Presentation type：Oral presentation (general)  

Venue：Baltimore, Maryland, USA   Country：United States  

Event date： 2016.3

Language：English   Presentation type：Oral presentation (general)  

Venue：Nagoya University, Nagoya, Japan   Country：Japan  

Event date： 2016.2

Language：English   Presentation type：Poster presentation  

Venue：東京大学　伊藤国際学術研究センター（東京都）   Country：Japan  

Event date： 2015.12

Language：English   Presentation type：Oral presentation (general)  

Venue：Nakamura Centenary Memorial Hall, Kyushu Institute of Technology (Tobata campus)   Country：Japan  

Event date： 2015.12

Language：English   Presentation type：Oral presentation (general)  

Venue：Honolulu, Hawaii, USA   Country：United States