Updated on 2021/05/31

写真a

 
KATO Keiko
 
Organization
Graduate School of Science Division of Material Science Physical Chemistry Associate professor
Graduate School
Graduate School of Science
Undergraduate School
School of Science Department of Chemistry
Title
Associate professor
External link

Degree 1

  1. 博士(理学) ( 2006.3   東京大学 ) 

Research Interests 5

  1. coherent phonon

  2. atto

  3. femto

  4. time-resolved

  5. ultrafast

Research Areas 1

  1. Natural Science / Semiconductors, optical properties of condensed matter and atomic physics  / ultrafast

Current Research Project and SDGs 1

  1. Ultrafast carrier and phonon dynamics observed by attosecond time-resolved measurements

Research History 6

  1. Nagoya University   Associate professor

    2021.1

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    Country:Japan

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  2. NTT物性科学基礎研究所   量子光物性研究部量子光デバイスグループ   主任研究員

    2014.4 - 2020.12

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  3. NTT物性科学基礎研究所   量子光物性研究部量子光デバイスグループ   研究主任

    2011.7 - 2014.3

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  4. NTT物性科学基礎研究所   量子光物性研究部量子光デバイスグループ   研究員

    2010.4 - 2011.6

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  5. NTT物性科学基礎研究所   量子光物性研究部量子光デバイスグループ   リサーチアソシエイト

    2008.7 - 2010.3

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  6. 物質・材料研究機構   ナノ計測センター超高速現象計測グループ   博士研究員

    2006.7 - 2008.6

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Education 1

  1. The University of Tokyo

    2003.4 - 2006.3

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Professional Memberships 3

  1. THE PHYSICAL SOCIETY OF JAPAN

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  2. THE JAPAN SOCIETY OF APPLIED PHYSICS

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  3. 分子科学会

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Awards 3

  1. NTT Science and Core Technology Laboratory Group, Research and Engineering Award

    2018  

    Hiroki Mashiko, Keiko Kato, Katsuya Oguri

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  2. NTT Basic Research Laboratories, Achievement Award

    2016  

    Hiroki Mashiko, Keiko Kato, Katsuya Oguri

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  3. Encouragement Award

    2007  

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Papers 22

  1. Highly sensitive transient reflection measurement in extreme ultraviolet region for tracking carrier and coherent phonon dynamics Reviewed

    Keiko Kato, Hiroki Mashiko, Yoji Kunihashi, Hiroo Omi, Hideki Gotoh, Katsuya Oguri

    Optics Express   Vol. 28 ( 2 ) page: 1595 - 1595   2020.1

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    Authorship:Lead author, Corresponding author   Publishing type:Research paper (scientific journal)   Publisher:The Optical Society  

    DOI: 10.1364/oe.381585

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  2. Relationship between the Fano asymmetry parameter and time-domain spectra studied by time-resolved measurement of carriers and phonons in p -type Si Reviewed

    Keiko Kato, Yuya Hasegawa, Katsuya Oguri, Takehiko Tawara, Tadashi Nishikawa, Hideki Gotoh

    Physical Review B   Vol. 97 ( 10 )   2018.3

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:American Physical Society  

    We performed time-resolved reflectivity measurements in p-type Si to study the Fano asymmetry parameter as a function of time-domain parameters. We observed a fast decay of intervalence band transitions, and slow decay of optical phonons, which respectively correspond to the continuum and discrete states. The experimental results revealed that the initial phase of the discrete state and the ratio of the relative transition amplitude between the discrete and continuum states affect the Fano asymmetry parameter. We derived an equation for the Fano asymmetry parameter as a function of the time-domain parameters that explained the experimental results. The present study indicates how the Fano asymmetry parameter is controlled by the time-domain parameters.

    DOI: 10.1103/PhysRevB.97.104301

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  3. Determination of phonon decay rate in p-type silicon under Fano resonance by measurement of coherent phonons Reviewed

    Keiko Kato, Katsuya Oguri, Haruki Sanada, Takehiko Tawara, Tetsuomi Sogawa, Hideki Gotoh

    AIP ADVANCES   Vol. 5 ( 9 )   2015.9

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:AMER INST PHYSICS  

    We determine phonon decay rate by measuring the temperature dependence of coherent phonons in p-type Si under Fano resonance, where there is interference between the continuum and discrete states. As the temperature decreases, the decay rate of coherent phonons decreases, whereas that evaluated from the Raman linewidth increases. The former follows the anharmonic decay model, whereas the latter does not. The different temperature dependences of the phonon decay rate of the two methods originate from the way that the continuum state, which originates from the Fano resonance, modifies the time-and frequency-domain spectra. The observation of coherent phonons is useful for evaluating the phonon decay rate free from the interaction with the continuum state and clarifies that the anharmonic decay is dominant in p-type Si even under Fano resonance. (C) 2015 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.

    DOI: 10.1063/1.4931393

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  4. Dynamical observation of photo-Dember effect on semi-insulating GaAs using femtosecond core-level photoelectron spectroscopy Reviewed

    Katsuya Oguri, Takanobu Tsunoi, Keiko Kato, Hidetoshi Nakano, Tadashi Nishikawa, Kouta Tateno, Tetsuomi Sogawa, Hideki Gotoh

    APPLIED PHYSICS EXPRESS   Vol. 8 ( 2 )   2015.2

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:IOP PUBLISHING LTD  

    We investigated ultrafast photogenerated carrier dynamics on a semi-insulating GaAs surface using femtosecond time-resolved core-level photoelectron spectroscopy. We observed a transient change in the surface potential where the Ga-3d core-level peak instantaneously shifted by similar to 350 meV toward a higher binding energy within 2 ps of a 100 fs laser irradiation. A comparison of the experimental results with numerical simulations based on a drift-diffusion model of a semi-insulating semiconductor revealed that the transient surface potential change was mainly due to the photo-Dember effect, whereby the large difference in the carrier diffusion between the electron and hole instantaneously induced a surface photovoltage. (C) 2015 The Japan Society of Applied Physics

    DOI: 10.7567/APEX.8.022401

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  5. The effect of n- and p-type doping on coherent phonons in GaN Reviewed

    Kunie Ishioka, Keiko Kato, Naoki Ohashi, Hajime Haneda, Masahiro Kitajima, Hrvoje Petek

    JOURNAL OF PHYSICS-CONDENSED MATTER   Vol. 25 ( 20 )   2013.5

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:IOP PUBLISHING LTD  

    The effect of doping on the carrier-phonon interaction in wurtzite GaN is investigated by pump-probe reflectivity measurements using 3.1 eV light in near resonance with the fundamental band gap of 3.39 eV. Coherent modulations of the reflectivity due to the E-2 and A(1)(LO) modes, as well as the 2A(1)(LO) overtone are observed. Doping of acceptor and donor atoms enhances the dephasing of the polar A(1)(LO) phonon via coupling with plasmons, with the effect of donors being stronger. Doping also enhances the relative amplitude of the coherent A(1)(LO) phonon with respect to that of the high-frequency E-2 phonon, though it does not affect the relative intensity in Raman spectroscopic measurements. We attribute this enhanced coherent amplitude to the transient depletion field screening (TDFS) excitation mechanism, which, in addition to impulsive stimulated Raman scattering (ISRS), contributes to the generation of coherent polar phonons even for sub-band gap excitation. Because the TDFS mechanism requires photoexcitation of carriers, we argue that the interband transition is made possible at a surface with photon energies below the bulk band gap through the Franz-Keldysh effect.

    DOI: 10.1088/0953-8984/25/20/205404

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  6. Decay and frequency shift of both intervalley and intravalley phonons in graphene: Dirac-cone migration Reviewed

    Ken-ichi Sasaki, Keiko Kato, Yasuhiro Tokura, Satoru Suzuki, Tetsuomi Sogawa

    PHYSICAL REVIEW B   Vol. 86 ( 20 )   2012.11

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:AMER PHYSICAL SOC  

    By considering analytical expressions for the self-energies of intervalley and intravalley phonons in graphene, we describe the behavior of D, 2D, and D' Raman bands with changes in doping (mu) and light-excitation energy (E-L). Comparing the self-energy with the observed mu dependence of the 2D bandwidth, we estimate the wave vector q of the constituent intervalley phonon at (h) over bar vq similar or equal to E-L/1.6 (v is the electron's Fermi velocity) and conclude that the self-energy makes a major contribution (60%) to the dispersive behavior of the D and 2D bands. The estimate of q is based on a concept of shifted Dirac cones in which the resonance decay of a phonon satisfying q >omega/v (omega is the phonon frequency) into an electron-hole pair is suppressed when mu < (<(h)over bar>vq - h omega)/2. We highlight the fact that the decay of an intervalley (and intravalley longitudinal optical) phonon with q = omega/v is strongly suppressed by electron-phonon coupling at an arbitrary mu. This feature is in contrast with the divergent behavior of an intravalley transverse optical phonon, which bears a close similarity to the polarization function relevant to plasmons.

    DOI: 10.1103/PhysRevB.86.201403

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  7. Time-Resolved Surface Photoelectron Spectroscopy of Photoexcited Electron and Hole Dynamics on GaAs Using 92 eV Laser Harmonic Source Reviewed

    Oguri Katsuya, Kato Keiko, Nishikawa Tadashi, Gotoh Hideki, Tateno Kouta, Sogawa Tetsuomi, Nakano Hidetoshi

    Jpn J Appl Phys   Vol. 51 ( 7 ) page: 72401 - 072401-6   2012.7

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:The Japan Society of Applied Physics  

    We have developed a time-resolved surface photoelectron spectroscopy system based on a 1.5 eV laser-pump and 92 eV high-order harmonic probe configuration that enables us to measure the electron and hole dynamics on a semiconductor surface. Core-level photoelectron spectra of GaAs(001) were successfully obtained with a single 59th harmonic, which was selected by using a pair of Mo/Si multilayer mirrors with a narrow reflection bandwidth. We observed transient energy shifts of the Ga 3d core level photoelectron peak of approximately 200 meV towards a higher binding energy, indicating that the surface potential changed due to the spatial separation of electron--hole pairs generated by the laser irradiation. The relatively slow recovery of the Ga 3d core level shift with a time constant of a few ns is dominated by the recombination process of the excess surface charges generated by the laser irradiation.

    DOI: 10.1143/JJAP.51.072401

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  8. Ultrafast carrier and coherent phonon dynamics in semi-insulated and n-type 4H-SiC Reviewed

    Keiko Kato, Katsuya Oguri, Atsushi Ishizawa, Hidetoshi Nakano, Tetsuomi Sogawa

    JOURNAL OF APPLIED PHYSICS   Vol. 111 ( 11 )   2012.6

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:AMER INST PHYSICS  

    We investigated ultrafast carrier and phonon dynamics in semi-insulated (SI) and n-type 4H-SiC using time-resolved reflectivity measurements. In the n-type 4H-SiC, carriers are excited by an inter-conduction band transition, and thermalized by electron-electron scattering within 20 fs. We observed coherent phonons of folded phonon modes, which become Raman active as a result of the zone folding, and those of A(1)-symmetry longitudinal optical (A(1)-LO) phonon mode. In the n-type SiC, the A(1)-LO coherent phonon forms a coupled mode with a plasmon, resulting in an asymmetrically broadened Fourier transform spectrum. The polarization dependence and the sine-type initial phase indicate that the impulsive stimulated Raman scattering is the mechanism generating coherent phonons of E-2-symmetry transverse optical and A(1)-LO modes in both the SI and n-type 4H-SiC. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4725479]

    DOI: 10.1063/1.4725479

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  9. Pseudospin for Raman D band in armchair graphene nanoribbons Reviewed

    Ken-ichi Sasaki, Keiko Kato, Yasuhiro Tokura, Satoru Suzuki, Tetsuomi Sogawa

    PHYSICAL REVIEW B   Vol. 85 ( 7 )   2012.2

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    By analytically constructing the matrix elements of an electron-phonon interaction for the D band in the Raman spectra of armchair graphene nanoribbons, we show that pseudospin and momentum conservation result in (i) a D band consisting of two components, (ii) a D band Raman intensity that is enhanced only when the polarizations of the incident and scattered light are parallel to the armchair edge, and (iii) the D band softening/hardening behavior caused by the Kohn anomaly effect is correlated with that of the G band. Several experiments are mentioned that are relevant to these results. It is also suggested that pseudospin is independent of the boundary condition for the phonon mode, while momentum conservation depends on it.

    DOI: 10.1103/PhysRevB.85.075437

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  10. High-order harmonic photoelectron spectroscopy system towards measuring attosecond electron dynamics on solid surfaces Reviewed

    Oguri K, Nakano H, Kato K, Nishikawa T, Ishizawa A, Gotoh H, Tateno K, Sogawa T

    Springer Proceedings in Physics   Vol. 125   page: 373 - 377   2012

  11. Theory of optical transitions in graphene nanoribbons Reviewed

    Ken-ichi Sasaki, Keiko Kato, Yasuhiro Tokura, Katsuya Oguri, Tetsuomi Sogawa

    PHYSICAL REVIEW B   Vol. 84 ( 8 )   2011.8

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    Matrix elements of electron-light interactions for armchair and zigzag graphene nanoribbons are constructed analytically using a tight-binding model. The changes in wave number (Delta n) and pseudospin are the necessary elements if we are to understand the optical selection rule. It is shown that incident light with a specific polarization and energy induces an indirect transition (Delta n = +/- 1), which results in a characteristic peak in the absorption spectra. Such a peak provides evidence that the electron standing wave is formed by multiple reflections at both edges of a ribbon. It is also suggested that the absorption of low-energy light is sensitive to the position of the Fermi energy, direction of light polarization, and irregularities in the edge. The effect of depolarization on the absorption peak is briefly discussed.

    DOI: 10.1103/PhysRevB.84.085458

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  12. Doping-type dependence of phonon dephasing dynamics in Si Reviewed

    Keiko Kato, Katsuya Oguri, Atsushi Ishizawa, Kouta Tateno, Takehiko Tawara, Hideki Gotoh, Masahiro Kitajima, Hidetoshi Nakano, Tetsuomi Sogawa

    APPLIED PHYSICS LETTERS   Vol. 98 ( 14 )   2011.4

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    We studied the dephasing dynamics of coherent phonons in n-type, p-type, and intrinsic Si using time-resolved reflectivity measurements with sub-10 fs laser pulses. The dephasing time of the coherent phonons increases (decreases) for n-type (p-type) doping compared with that of intrinsic Si, while the frequencies of the coherent phonons exhibit a redshift for both types of doping. These doping-induced changes in the coherent phonon dynamics are observed when the carrier concentration exceeds 10(19) cm(-3). The doping-type dependent changes in the dephasing time are attributed to the interconduction and intervalence band transitions in n-type and p-type Si, respectively. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3574533]

    DOI: 10.1063/1.3574533

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  13. Observation of coherent phonons in metallic carbon nanotubes Reviewed

    Keiko Kato, Katsuya Oguri, Atsushi Ishizawa, Hideki Gotoh, Hidetoshi Nakano, Tetsuomi Sogawa

    APPLIED PHYSICS LETTERS   Vol. 97 ( 12 )   2010.9

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    We investigated the ultrafast dynamics of coherent phonons with sub-10 fs laser pulses in metallic single-walled carbon nanotubes (m-SWCNTs). We identified radial breathing mode (RBM), D-mode, and G-mode coherent phonons in m-SWCNTs. We also resolved G(-)- and G(+)-mode coherent phonons, which correspond to the longitudinal and transverse optical phonon modes, respectively. The frequencies of the RBM coherent phonons shift with increases in laser intensity, suggesting that photocarriers modify the phonon frequency. (C) 2010 American Institute of Physics. [doi:10.1063/1.3491220]

    DOI: 10.1063/1.3491220

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  14. Dynamics of coherent phonons in disordered graphite Reviewed

    Ikufumi Katayama, Sho Koga, Toru Shimada, Keiko Kato, Shunichi Hishita, Daisuke Fujita, Jun Takeda, Masahiro Kitajima

    International Conference on Ultrafast Phenomena     2010

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    DOI: 10.1364/up.2010.tue42

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  15. Ultrafast coherent phonon dynamics in metallic singlewalled carbon nanotubes Reviewed

    Kato K, Ishizawa A, Oguri K, Gotoh H, Nakano H, Sogawa T

    Optics InfoBase Conference Papers     2010

  16. Optical control and mode selective excitation of coherent phonons in YBa2Cu3O7-delta Reviewed

    Hiroshi Takahashi, Keiko Kato, Hidetoshi Nakano, Masahiro Kitajima, Kenji Ohmori, Kazutaka G. Nakamura

    SOLID STATE COMMUNICATIONS   Vol. 149 ( 43-44 ) page: 1955 - 1957   2009.11

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:PERGAMON-ELSEVIER SCIENCE LTD  

    Femtosecond time-resolved reflectivity measurement is performed on YBa2Cu3O7-delta films. Coherent phonons of both the Ba-O and Cu-O modes are observed at frequencies of 3.4 and 4.3 THz, respectively. Amplitudes of both Ba-O and Cu-O modes are optically manipulated by using a pair of femtosecond pulses, the separation time of which is controlled. Coherent phonons of the Ba-O and Cu-O modes are completely suppressed at the double-pulse separation times of 135.0 and 108.5 fs and those amplitudes are enhanced at 270 and 217 fs, respectively. (C) 2009 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/j.ssc.2009.07.037

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  17. Anisotropy in Ultrafast Carrier and Phonon Dynamics in p-Type Heavily Doped Si Reviewed

    Keiko Kato, Atsushi Ishizawa, Katsuya Oguri, Kouta Tateno, Takehiko Tawara, Hideki Gotoh, Masahiro Kitajima, Hidetoshi Nakano

    JAPANESE JOURNAL OF APPLIED PHYSICS   Vol. 48 ( 10 )   2009.10

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:JAPAN SOCIETY APPLIED PHYSICS  

    We performed time-resolved reflectivity measurements in p-type heavily doped Si under non-resonant excitation. A large contribution from anisotropic state-filling is observed, indicating that the lowered Fermi energy due to the p-type heavy doping enhances the anisotropy in the hole distribution. The initial phase shift of coherent phonons induced by p-type doping is attributed to the anisotropic hole distribution. (C) 2009 The Japan Society of Applied Physics

    DOI: 10.1143/JJAP.48.100205

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  18. Dephasing dynamics of coherent phonons in heavily doped Si under non-resonant photoexcitation Reviewed

    Kato K, Ishizawa A, Oguri K, Tateno K, Tawara T, Kitajima M, Nakano H

    Optics InfoBase Conference Papers     2009

  19. Ultrafast dynamics of coherent phonons in the aligned single-walled carbon nanotubes Reviewed

    Keiko Kato, Kunie Ishioka, Masahiro Kitajima, Jie Tang, Hrvoje Petek

    ULTRAFAST PHENOMENA XVI   Vol. 92   page: 259 - +   2009

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    Language:English   Publishing type:Research paper (international conference proceedings)   Publisher:SPRINGER-VERLAG BERLIN  

    Sub-10-fs pulses allow real time observation of coherent phonons in aligned bundles of single-walled carbon nanotubes. A complex polarization dependence of the G band phonon amplitude in the transient reflectivity is explained by the superposition of G-band phonons with different symmetries.

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  20. Coherent Phonon Anisotropy in Aligned Single-Walled Carbon Nanotubes Reviewed

    Keiko Kato, Kunie Ishioka, Masahiro Kitajima, Jie Tang, Riichiro Saito, Hrvoje Petek

    NANO LETTERS   Vol. 8 ( 10 ) page: 3102 - 3108   2008.10

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    By time-resolved reflectivity measurements with sub-10 fs laser pulses at 395 nm, the coherent phonons of aligned bundles of single-walled carbon nanotubes are observed for various polarization directions of the pump and probe pulses. In the isotropic reflectivity measurement, we observe the radial breathing modes, G, and even D modes, while in the anisotropic reflectivity mode, only the G mode appears. A complex polarization dependence of the G band phonon amplitude in the isotropic reflectivity is explained by the superposition of G band phonons with different symmetries.

    DOI: 10.1021/nl801200p

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  21. Dissociative ATI of H2and D2in intense soft x-ray laser fields Reviewed

    K Hoshina, A Hishikawa, K Kato, T Sako, K Yamanouchi, E J Takahashi, Y Nabekawa, K Midorikawa

    Journal of Physics B: Atomic, Molecular and Optical Physics   Vol. 39 ( 4 ) page: 813 - 829   2006.2

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    DOI: 10.1088/0953-4075/39/4/007

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  22. Photodecomposition reaction of trapped aniline cation by photofragment excitation spectroscopy Reviewed

    Keiko Kato, Kaoru Yamanouchi

    Chemical Physics Letters   Vol. 397 ( 1-3 ) page: 237 - 241   2004.10

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    Authorship:Lead author   Publishing type:Research paper (scientific journal)   Publisher:Elsevier BV  

    DOI: 10.1016/j.cplett.2004.08.123

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MISC 53

  1. Determination of geometrical structure of CCl3+ by trapped-ion electron diffraction

        2021.3

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  2. 過渡反射/屈折分光法を用いたアト秒電子物性の解明 Invited

    増子拓紀, 加藤景子, 小栗克弥, 大島彬広, 山﨑友奨, Ming-Chang Chen, 片山郁文, 武田淳

        2021.3

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  3. 高次高調波ベース時間分解ARPESを用いたWSe2の光励起初期過程ダイナミクス

    山口大也, 加藤景子, 増子拓紀, 関根佳明, 日比野浩樹, 片山郁文, 武田淳, 小栗克弥

    レーザー学会学術講演会第41回年次大会     2021.1

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  4. 時間分解ARPESによるWSe2の超高速バレー間緩和過程の測定

    山口大也, 加藤景子, 増子拓紀, 関根佳明, 日比野浩樹, 片山郁文, 武田淳, 小栗克弥

    第81回応用物理学会秋季学術講演会     2020.9

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  5. アト秒高次高調波で探るペタヘルツスケール光物性 Invited

    小栗克弥, 増子拓紀, 加藤景子

    応用物理学会「量子ビームによる表面界面の光機能探究研究会」第2回     2020.6

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  6. サブ5fs時間分解ARPESを用いたグラファイトにおける非平衡光励起キャリアの超高速緩和過程の観測

    小栗克弥, 當銘健人, 當銘健人, 増子拓紀, 加藤景子, 関根佳明, 日比野浩樹, 日比野浩樹, 須田亮, 後藤秀樹

    日本物理学会講演概要集(CD-ROM)   Vol. 73 ( 2 ) page: ROMBUNNO.11pA116‐9   2018.9

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  7. n型単層エピタキシャルグラフェンにおける非平衡キャリア緩和ダイナミクスのサブ5fs時間分解ARPES計測

    當銘賢人, 當銘賢人, 小栗克弥, 増子拓紀, 加藤景子, 関根佳明, 日比野浩樹, 日比野浩樹, 須田亮, 後藤秀樹

    応用物理学会秋季学術講演会講演予稿集(CD-ROM)   Vol. 79th   page: ROMBUNNO.21p‐211A‐14   2018.9

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  8. Ultrafast relaxation of nonequlibrium photoexcited carrier in graphite probed by sub-5-fs high-harmonic-based ARPES

    Oguri Katsuya, Toume Kento, Mashiko Hiroki, Kato Keiko, Sekine Yoshiaki, Hibino Hiroki, Suda Akira, Gotoh Hideki

    Meeting Abstracts of the Physical Society of Japan   Vol. 73 ( 0 ) page: 1057 - 1057   2018

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    Language:Japanese   Publisher:一般社団法人 日本物理学会  

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  9. 準モノサイクルパルスを用いた高次高調波発生による時間分解ARPES‐吸収分光複合システムの開発

    當銘賢人, 當銘賢人, 小栗克弥, 増子拓紀, 加藤景子, 須田亮, 後藤秀樹

    応用物理学会秋季学術講演会講演予稿集(CD-ROM)   Vol. 78th   page: ROMBUNNO.6a‐S45‐4   2017.8

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  10. ファノ共鳴におけるコヒーレントフォノンの初期位相シフトの観測

    加藤景子, 長谷川祐哉, 長谷川祐哉, 小栗克弥, 西川正, 後藤秀樹

    応用物理学会春季学術講演会講演予稿集(CD-ROM)   Vol. 63rd   page: ROMBUNNO.21A-S622-12   2016.3

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  11. 時間分解分光によるp型Siにおけるファノ干渉の観測

    長谷川祐哉, 長谷川祐哉, 加藤景子, 小栗克弥, 西川正, 後藤秀樹

    光物性研究会論文集   Vol. 27th   page: 299‐302   2016

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  12. Time‐Resolved Observation of Photo‐Generated Carrier Transport Dynamics on Semiconductor Surface Based on Femtosecond Core‐Level Photoelectron Spectroscopy

    小栗克弥, 角井貴信, 加藤景子, 中野秀俊, 西川正, 舘野功太, 寒川哲臣, 後藤秀樹

    レーザー研究   Vol. 43 ( 12 ) page: 844 - 851   2015.12

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  13. Time-Resolved Observation of Photo-Generated Carrier Transport Dynamics on Semiconductor Surface Based on Femtosecond Core-Level Photoelectron Spectroscopy

    小栗 克弥, 角井 貴信, 加藤 景子

    レーザー研究 = The review of laser engineering : レーザー学会誌   Vol. 43 ( 12 ) page: 844 - 851   2015.12

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  14. フェムト秒時間分解内殻光電子分光法によるGaAs表面の動的光デンバー効果の観測

    小栗克弥, 角井貴信, 加藤景子, 中野秀俊, 西川正, 舘野功太, 寒川哲臣, 後藤秀樹

    日本物理学会講演概要集(CD-ROM)   Vol. 70 ( 1 ) page: ROMBUNNO.24ACP-10   2015.3

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  15. シリコンのコヒーレントフォノンの発生起源に関する実験的考察

    加藤景子, 小栗克弥, 後藤秀樹

    応用物理学会春季学術講演会講演予稿集(CD-ROM)   Vol. 62nd   page: ROMBUNNO.14P-A15-7   2015.2

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  16. 24aCP-10 Time-resolved study of photo-Dember effect on semi-insulating GaAs using femtosecond core-level photoelectron spectroscopy

    Oguri K, Tsunoi T, Kato K, Nakano H, Nishikawa T, Tateno K, Sogawa T, Gotoh H

    Meeting Abstracts of the Physical Society of Japan   Vol. 70 ( 0 )   2015

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  17. 分子イオンの幾何学的構造決定のためのイオントラップ電子回折装置

    田中秀昂, 加藤景子, 歸家令果, 山内薫

    分子科学討論会講演プログラム&要旨(Web)   Vol. 9th   page: ROMBUNNO.1P012 (WEB ONLY)   2015

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  18. 高ドープシリコンのコヒーレントフォノン緩和ダイナミクスにおける温度依存性

    加藤景子, 小栗克弥, 眞田治樹, 俵毅彦, 寒川哲臣, 後藤秀樹

    応用物理学会秋季学術講演会講演予稿集(CD-ROM)   Vol. 75th   page: ROMBUNNO.19A-C2-5   2014.9

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  19. 時間分解自己回折法によるCVDグラフェンの位相緩和時間測定

    玉城智啓, 小栗克弥, 増子拓紀, 加藤景子, 中野秀俊

    応用物理学会春季学術講演会講演予稿集(CD-ROM)   Vol. 61st   page: ROMBUNNO.17P-F7-1   2014.3

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  20. Coherent phonon dynamics in carbon nanotubes

    Keiko Kato, Katsuya Oguri, Masahiro Kitajima

    Springer Series in Optical Sciences   Vol. 180   page: 105 - 127   2014

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    DOI: 10.1007/978-3-642-40594-5_6

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  21. グラフェンにおけるラマンスペクトルと電子スペクトルのドーピング依存性

    佐々木健一, 加藤景子, 都倉康弘, 鈴木哲, 寒川哲臣

    日本物理学会講演概要集   Vol. 67 ( 2 ) page: 769   2012.8

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  22. アームチェアエッジにおけるラマンDバンドの擬スピン

    佐々木健一, 加藤景子, 都倉康弘, 鈴木哲, 寒川哲臣

    日本物理学会講演概要集   Vol. 67 ( 1 ) page: 914   2012.3

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  23. 液体ヘリウム温度におけるグラファイトのコヒーレントフォノンダイナミクス

    加藤景子, 小栗克弥, 眞田治樹, 俵毅彦, 後藤秀樹, 西川正, 寒川哲臣

    応用物理学関係連合講演会講演予稿集(CD-ROM)   Vol. 59th   page: ROMBUNNO.18A-E9-10   2012.2

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  24. 高次高調波を用いたフェムト秒時間分解表面光電子分光による過渡表面光起電力効果の観測

    小栗克弥, 角井貴信, 角井貴信, 加藤景子, 中野秀俊, 西川正, 後藤秀樹, 舘野功太, 片山郁文, 武田淳, 寒川哲臣

    応用物理学関係連合講演会講演予稿集(CD-ROM)   Vol. 59th   page: ROMBUNNO.18A-E9-11   2012.2

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  25. 19aEC-7 Self-Energies of Phonons and Electrons : Dirac Cone Migration

    Sasaki K, Kato K, Tokura Y, Suzuki S, Sogawa T

    Meeting Abstracts of the Physical Society of Japan   Vol. 67 ( 0 )   2012

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  26. 26pSB-2 Pseudospin for Raman D Band of Armchair Graphene Edge

    Sasaki K, Kato K, Tokura Y, Suzuki S, Sogawa T

    Meeting Abstracts of the Physical Society of Japan   Vol. 67 ( 0 )   2012

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  27. グラファイトにおけるコヒーレントDモードフォノンの検出波長依存性

    古賀翔, 土井幸司郎, 片山郁文, 高田透, 加藤景子, 菱田俊一, 藤田大介, 武田淳, 北島正弘

    日本物理学会講演概要集   Vol. 66 ( 2 ) page: 859   2011.8

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  28. 22aTE-8 Probe wavelength dependence of coherent D-mode phonon in graphite

    Koga S, Doi K, Katayama I, Shimada T, Kato K, Hishita S, Fujita D, Takeda J, Kitajima M

    Meeting Abstracts of the Physical Society of Japan   Vol. 66 ( 0 )   2011

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  29. Time-resolved observation of surface photovoltage effect on GaAs surface with high-order harmonic pulse source

    OGURI K, KATO K, NISHIKAWA T, GOTOH H, TATENO K, SOGAWA T, NAKANO H

    レーザー学会研究会報告 = Reports on the Topical meeting of the Laser Society of Japan   Vol. 407   page: 11 - 15   2010.12

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  30. 59次高調波パルスを用いたポンププローブ型半導体表面光電子分光

    小栗克弥, 加藤景子, 西川正, 後藤秀樹, 舘野功太, 寒川哲臣, 中野秀俊

    応用物理学会学術講演会講演予稿集(CD-ROM)   Vol. 71st   page: ROMBUNNO.16P-D-14   2010.8

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  31. フェムト秒レーザによるSiCのコヒーレントフォノンの観測

    加藤景子, 石澤淳, 小栗克弥, 中野秀俊, 寒川哲臣

    応用物理学会学術講演会講演予稿集(CD-ROM)   Vol. 71st   page: ROMBUNNO.16P-D-19   2010.8

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  32. カーボンナノチューブのコヒーレントフォノンにおける環境効果

    加藤景子, 高木大輔, 小林慶裕, 日比野浩樹, 石澤淳, 小栗克弥, 後藤秀樹, 中野秀俊

    応用物理学関係連合講演会講演予稿集(CD-ROM)   Vol. 57th   page: ROMBUNNO.19P-F-16   2010.3

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  33. 金属型単層カーボンナノチューブのコヒーレントフォノンに及ぼす光励起キャリアの影響

    加藤景子, 石澤淳, 小栗克弥, 後藤秀樹, 中野秀俊

    応用物理学関係連合講演会講演予稿集(CD-ROM)   Vol. 57th   page: ROMBUNNO.19P-F-15   2010.3

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  34. サブ10fsレーザーを用いたYBa<sub>2</sub>Cu<sub>3</sub>O<sub>7-δ</sub>のコヒーレントフォノン計測

    高橋弘史, 加藤景子, 石澤淳, 小栗克弥, 中野秀俊, 中村一隆

    応用物理学関係連合講演会講演予稿集(CD-ROM)   Vol. 57th   page: ROMBUNNO.19P-F-13   2010.3

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  35. グラファイトのコヒーレントD‐モードフォノン

    古賀翔, 片山郁文, 武田淳, 島田透, 加藤景子, 菱田俊一, 藤田大介, 北島正弘

    応用物理学関係連合講演会講演予稿集(CD-ROM)   Vol. 57th   page: ROMBUNNO.19P-F-14   2010.3

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  36. カーボン系材料におけるコヒーレントフォノンのプラズモン増強

    古賀翔, 片山郁文, 武田淳, 首藤健一, 島田透, 加藤景子, 菱田俊一, 藤田大介, 北島正弘

    日本物理学会講演概要集   Vol. 65 ( 1 ) page: 806   2010.3

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  37. 金属型カーボンナノチューブのGモードのコヒーレントフォノンの観測

    加藤景子, 石澤淳, 小栗克弥, 後藤秀樹, 中野秀俊

    日本物理学会講演概要集   Vol. 65 ( 1 ) page: 858   2010.3

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  38. Real‐Time Observation of Ultrafast Carrier and Phonon Dynamics in p‐Type Silicon

    加藤景子, 石澤淳, 小栗克弥, 舘野功太, 俵毅彦, 後藤秀樹, 中野秀俊

    レーザー研究   Vol. 38 ( 2 ) page: 130 - 135   2010.2

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  39. 20pGS-6 Observation of G-mode coherent phonons in metallic carbon nanotubes

    Kato Keiko, Ishizawa Atsushi, Oguri Katsuya, Gotoh Hideki, Nakano Hidetoshi

    Meeting Abstracts of the Physical Society of Japan   Vol. 65 ( 0 )   2010

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  40. Coherent phonons in carbon nanotubes

    Keiko Kato, Masahiro Kitajima

    Journal of the Vacuum Society of Japan   Vol. 53 ( 5 ) page: 317 - 326   2010

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    Carbon nanotubes have potential to make breakthrough achievement in nano-electronics, photonics, and ultrafast devices. We report real-time observations of coherent phonons in aligned single-walled carbon nanotubes through the time-resolved reflectivity measurements with sub-10 fs laser pulses. In the isotropic reflectivity measurements, we observe the radial breathing modes, G and even D modes, while in the anisotropic reflectivity measurements, only the G mode appears. A complex polarization dependence of the G band phonon amplitude in the isotropic reflectivity indicates the superposition of G band phonons with different symmetries.

    DOI: 10.3131/jvsj2.53.317

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  41. 23aPS-41 Plasmon-enhanced coherent phonons in carbon materials

    Koga S, Katayama I, Takeda J, Shudo K, Shimada T, Kato K, Hishita S, Fujita D, Kitajima M

    Meeting Abstracts of the Physical Society of Japan   Vol. 65 ( 0 )   2010

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  42. 時間分解表面光電子分光に向けた数サイクルレーザパルス励起高次高調波の発生

    小栗克弥, 石澤淳, 加藤景子, 西川正, 中野秀俊

    応用物理学会学術講演会講演予稿集   Vol. 70th ( 3 ) page: 1004   2009.9

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  43. p型Siにおけるコヒーレントフォノンダイナミクス

    加藤景子, 石澤淳, 小栗克弥, 舘野功太, 俵毅彦, 中野秀俊

    応用物理学関係連合講演会講演予稿集   Vol. 56th ( 3 ) page: 1138   2009.3

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  44. YBa<sub>2</sub>Cu<sub>3</sub>O<sub>7-δ</sub>におけるコヒーレントフォノンのモード選択励起

    高橋弘史, 久木宮領, 中村一隆, 加藤景子, 中野秀俊, 北島正弘, 大森賢治

    応用物理学関係連合講演会講演予稿集   Vol. 56th ( 3 ) page: 1138   2009.3

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  45. 炭素系材料におけるコヒーレントフォノンとその欠陥効果

    古賀翔, 片山郁文, 武田淳, 島田透, 加藤景子, 藤田大介, 北島正弘

    光物性研究会論文集   Vol. 20th   page: 65 - 68   2009

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  46. 高温超伝導酸化物(YBa<sub>2</sub>Cu<sub>3</sub>O<sub>7-δ</sub>)のコヒーレントフォノンと制御

    高橋弘史, 高橋弘史, 久木宮領, 加藤景子, 中野秀俊, 北島正弘, 大森賢治, 中村一隆

    分子科学討論会講演プログラム&amp;要旨(Web)   Vol. 3rd   page: ROMBUNNO.4C01 (WEB ONLY)   2009

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  47. 単層カーボンナノチューブのコヒーレント振動ダイナミクス

    加藤景子, 石岡邦江, 北島正弘, TANG Jie, PETEK Hrvoje

    応用物理学関係連合講演会講演予稿集   Vol. 55th ( 3 ) page: 1138   2008.3

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  48. カーボンナノチューブにおける超高速電子・格子ダイナミクス

    加藤景子, 石岡邦江, 北島正弘, TANG Jie, PETEK Hrvoje

    応用物理学会学術講演会講演予稿集   Vol. 68th ( 3 ) page: 1108   2007.9

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  49. 単層カーボンナノチューブの超高速コヒーレント振動ダイナミクス

    加藤景子, 石岡邦江, 北島正弘, 唐捷, PETEK Hrvoje

    分子科学討論会講演要旨集(CD-ROM)   Vol. 1st   page: 2B02   2007.8

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  50. イオントラップ電子回折装置の開発:分子イオンの構造決定への応用

    加藤景子, 歸家令果, 山内薫

    化学反応討論会講演要旨集   Vol. 22nd   page: 90   2006.6

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  51. アニリンカチオンの光化学反応:イオントラップ質量分析法によるアプローチ

    加藤景子, 山内薫

    光化学討論会講演要旨集   Vol. 2003   page: 254   2003.11

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  52. イオントラップ質量分析法によるアニリンカチオンの光解離過程の追跡

    加藤景子, 山内薫

    分子構造総合討論会講演要旨集(CD-ROM)   Vol. 2003   page: 4PP097   2003.9

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  53. イオントラップ質量分析法による光解離反応の追跡:アニリンカチオンヘの応用

    加藤景子, 山内薫

    原子衝突研究協会研究会講演概要集   Vol. 28th   page: 119   2003.8

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KAKENHI (Grants-in-Aid for Scientific Research) 7

  1. Petaherz-scale solid state physics exploring by attosecond high-harmonic-based ultrafast spectroscopy

    Grant number:20H05670  2020.8 - 2025.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (S)  Grant-in-Aid for Scientific Research (S)

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  2. ペタヘルツスピントロニクスの創出

    Grant number:20H00358  2020.4 - 2024.3

    日本学術振興会  科学研究費助成事業 基盤研究(A)  基盤研究(A)

    小栗 克弥

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    既存の最高品質の高周波を遙かに凌駕する精度で制御可能となった光は、ペタヘルツ(PHz: 1015 Hz)周波数で物質中の電子を精密に操ることができる電界(PHz波)である。本研究では、計測・材料・理論の3チームが結集することによって、独自のアト秒(10-18秒)時間分解スピン計測プラットフォームを実現し、光波電界(PHz波)と、電子スピン・擬スピンなどのスピン自由度との相互作用ダイナミクスを明らかにする。これにより、従来のスイッチング速度限界を超えた”ペタヘルツスピントロニクス”を創造すると共に、PHz波の極限高速スピン自由度操作に基づく新しいスピントロニクスデバイスの基本原理を探求する。

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  3. アト秒時間分解オペランド計測法の開発と応用

    Grant number:20H02703  2020.4 - 2023.3

    日本学術振興会  科学研究費助成事業 基盤研究(B)  基盤研究(B)

    加藤 景子

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    Grant amount:\17940000 ( Direct Cost: \13800000 、 Indirect Cost:\4140000 )

    動作環境下(オペランド)にあるデバイスにおいて、アト秒時間領域で起きる電子・正孔の生成・緩和過程の実時間観測を通じ、デバイスの動作機構の解明を行う。そしてデバイスの高効率化・機能向上に向けた知見の獲得を目指す。本申請の遂行によりアト秒時間領域における電子応答特性の評価を行い、電子・光デバイスの高効率化・機能性向上のための新たなデバイスの物性・機能評価法を確立する。

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  4. ペタヘルツ電子振動応答を用いた光物性起源の解明とアト秒時間制御

    Grant number:19H02637  2019.4 - 2022.3

    日本学術振興会  科学研究費助成事業 基盤研究(B)  基盤研究(B)

    増子 拓紀

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    可視・紫外領域の光電界により誘起される分極応答(誘電分極)は、ペタヘルツ(1015 Hz:PHz)級の高い周波数を有するため、超高速の運動過程を持つ電子の振動応答が強く寄与している。これらの電子振動は、吸収・反射・屈折・発光・電流等の様々な光物性現象を生み出し、発光ダイオードや太陽電池、光合成等を通して我々の生活に欠かせない物理応答となっている。本研究では、新規的かつ高感度計測が可能なアト秒屈折分光法の実現を目指すと共に、電子・光デバイスの電子応答特性の解明に向けた挑戦を行い、アト秒科学分野を新領域に展開すると共に、産業界においても重要な役割を創出することを目標とする。
    可視・紫外領域の光電界は、ペタヘルツ(1015 Hz)級の周波数に達し、誘起される電子分極は、光物質相互作用に伴う様々な物理現象を生み出す。本研究では、アト秒(10-18 秒: as)パルスを用いて、固体物質内部で生じる電子分極応答(吸収・屈折・電流・光合成)の物理起源の解明およびアト秒時間制御に挑戦する。本研究は3つの主課題に分けられる:【課題1】ダブルアト秒パルスを用いた屈折分光法の確立、【課題2】pn接合半導体の初期電子応答の解明、【課題3】光合成の初期化学反応過程の解明。
    初年度(2019年度)は【課題1】に対して、超広帯域連続スペクトルを持つダブルアト秒パルスを用いた位相干渉計測に成功した。これにより超高時間分解能を持つアト秒位相分光の実現が可能となる。この位相計測法は、物質中で運動する電子の波動性(複素屈折率、複素誘電率、波束、双極子位相、分散など)を知る上で重要な技術と成り得る。本成果は、Optics Express米科学誌[H. Mashiko et al., Opt. Express(投稿中)]に投稿され、電気学会誌[論文番号0QD-20-019(印刷中)]、会議発表6件、ALPS2020国際会議にて優秀学生発表賞(横国大:大島氏)に採択される等の多数の成果を得ている。
    一方で、【課題2】に対して、我々は固体物質を用いた高感度なアト秒過渡反射実験に成功した。光子数の乏しい極端紫外アト秒パルスの弱点を克服するため、ロックイン増幅を組み合わせた実験系を構築し、ビスマス金属材料のコヒーレントフォノン現象の観測に成功した。この成果は、Optics Express米科学誌[Keiko Kato, Hiroki Mashiko et al., Opt. Express 28, 1595 (2020)]に採択され、会議発表5件の成果を残している。
    初年度(2019年度)は主に【課題1:ダブルアト秒パルスを用いた屈折分光法の確立】に取り組んでいる。具体的な実験内容を後述する。過去に代表研究者(申請者)が開発した二重光学ゲート(DOG:double optical gating)法を用いて発生した極端紫外領域の単一アト秒パルス(IAP: isolated attosecond pulse)は、広帯域の連続スペクトルを持つ (光子エネルギー帯域 : 25-40 eV)。このIAPは、本研究で開発された高時間分解能 (遅延分解能 : 0.6 as) かつ高安定 (遅延揺らぎ:2.6 as) の空間分割ミラーに入射される。分割されたIAP対が構築するスペクトル位相干渉画像(遅延ステップ:12 as)において、83-138 as 周期振動がIAP連続スペクトル全域において観測された。干渉画像より得られるAC成分 (25-40 eV) からIAP対の位相情報を抽出することが可能であり、新たな超高速位相分光計測の実現性を示唆している。本成果により、論文2件(内1件投稿中)、会議発表6件、受賞1件の成果を得ている。
    一方で、【課題2:pn接合半導体の初期電子応答の解明】に向けて、我々は固体物質を用いた高感度なアト秒過渡反射実験に成功した。本研究では、ロックイン増幅検出を組み合わせた実験系を開発し、ビスマス金属材料のコヒーレントフォノン現象の観測に成功した。過去のアト秒パルスを用いた分光実験は、主に検出感度が数%だったのに対して、本実験では0.01%程度の検出感度を誇る。これにより、今まで観測不可能であった微小な電子応答の変化を捉えることが可能となり、金属・半導体・絶縁体材料の電子物性調査に対する強力な分析ツールになると期待される。本成果により、論文1件、会議発表5件の成果を得ている。
    今後は、2019年度に開発した「ダブルアト秒スペクトル干渉系」および「ロックイン増幅器を用いたアト秒過渡反射分光系」の技術を応用し、半導体・絶縁体材料をターゲットに用いて、物質中の電子の複素応答(屈折率や誘電率)を解明する実験を行い、新たな電子物性の解明を試みる。
    初めに、【課題1:ダブルアト秒パルスを用いた屈折分光法の確立】に対しては、窒素分子(N2)およびシリコンカーバイド(SiC)半導体ターゲットを用いる予定である。新規的な技術であるダブルアト秒位相分光を通して、これらの材料の過渡的な電子波動性(波束、双極子位相、分散、複素屈折率、複素誘電率)を理解することは、結果的に次世代のアト秒コヒーレント制御技術に繋がる期待がある。従来の振幅(強度)検出では解明できなかった物質応答の根幹である原子散乱係数を決定することにより、新たな超高速電子物性の研究領域の創生に挑戦する。
    次に、【課題2:pn接合半導体の初期電子応答の解明】に向けて、半導体の代表的な材料でもあるpn(もしくはpin)接合のSi半導体をターゲットに用いる。pn接合シリコン半導体系の電子振動(過渡反射分光)および光起電流の相関関係を捉える実験は、現在のGHzを超えるPHz高速通信や演算処理の基礎動作原理に繋がる可能性がある。また、この光起電流は太陽電池の動作原理でもあり、光電変換に伴う初期電子運動を捉える研究は、その量子効率や損失等の改善に役立つと期待される。

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  5. Development of attosecond spectroscopic techniques for solid state materials towards petahertz engineering

    Grant number:16H02120  2016.4 - 2020.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)  Grant-in-Aid for Scientific Research (A)

    Oguri Katsuya

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    We have developed an isolated attosecond pulse source whose bandwidth corresponds to 30-as duration assuming Fourier limit based on based on a 1.6-cycle Ti:sapphire laser pulse, a time-resolved and angle-resolved photoelectron spectroscopy (Tr-ARPES) with sub-5fs-probe resolution that will enable subcycle electronic band mapping, and a time-resolved reflectivity measurement with much higher sensitivity than previous high-order harmonic spectroscopic techniques. By using our developed attosecond spectroscopic techniques, we have demonstrated a time-domain measurement of PHz-dipole oscillation in sapphire crystal, and Tr-ARPES measurement of the ultrafast evolution of energy redistribution process in photoexcited graphite. These newly developed attosecond spectroscopic techniques and ultrafast electronic dynamics in solid state materials will contribute to future development of PHz-driven solid state devices.

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  6. Study of ultrafast dynamics in graphene by using high-order haromonic photoelectron spectroscopy

    Grant number:23310086  2011.4 - 2014.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)  Grant-in-Aid for Scientific Research (B)

    OGURI Katsuya

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    To clarify ultrafast relaxation dynamics in high quality and large-area graphene which is grown on a silicon carbide substarate by sublimating silicon, we have developed femtosecond time-resolved surface photoelectron spectroscopy based on a high-order harmonics source. By using this system, we clarified the surfce transport of photoexcited electron and hole on a semiconductor surface, thus showing the potential of this system for measuring ultrafast relaxation dynamics in graphene. We have also studied the surface-enhanced Raman scattering (SERS)of graphene grown on SiC by depositing Ag. The enhancement of the Raman spectrum in graphene reached more than 60. Moreover, we have successfully estimated a electron dephasing time of monolayer graphene to be approxiamtely 50 fs by using a time-resolved transient diffraction technique.

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  7. Ultrafast dynamics in solids studied by carrier-envelope phase locked laser pulses

    Grant number:20750021  2008 - 2010

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Young Scientists (B)  Grant-in-Aid for Young Scientists (B)

    KATO Keiko

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    Authorship:Principal investigator 

    Grant amount:\4810000 ( Direct Cost: \3700000 、 Indirect Cost:\1110000 )

    We performed time-resolved reflectivity measurements to study ultrafast carrier and phonon dynamics by carrier-envelope phase locked laser pulses. In heavily doped Si, the anisotropic hole-distribution drives coherent phonons. In metallic single-walled carbon nanotube, we found the coupling between carriers and coherent phonons.

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Industrial property rights 1

  1. 半導体の特性測定方法

    加藤 景子, 小栗 克弥, 中野 秀俊

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    Applicant:日本電信電話株式会社

    Application no:特願2009-139989  Date applied:2009.6

    Announcement no:特開2010-287712  Date announced:2010.12

    J-GLOBAL

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Teaching Experience (Off-campus) 1

  1. 先端光科学実験実習 非常勤講師

    2010.4 - 2013.3 The University of Tokyo)

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