Updated on 2022/05/25

写真a

 
OKAWA, Mario
 
Affiliation
Faculty of Science and Engineering, School of Advanced Science and Engineering
Job title
Assistant Professor(non-tenure-track)

Education

  • 2008.03
    -
    2011.04

    University of Tokyo   Graduate School of Frontier Sciences   Department of Advanced Materials Science (Ph.D. course)  

  • 2006.04
    -
    2008.03

    University of Tokyo   Graduate School of Frontier Sciences   Department of Advanced Materials Science (Master's degree course)  

  • 2002.04
    -
    2006.03

    Tokyo University of Science   Faculty of Science Division I   Department of Applied Physics  

Degree

  • University of Tokyo   Ph.D.

Research Experience

  • 2022.04
    -
    Now

    Waseda University   School of Advanced Science and Engineering   Assistant Professor

  • 2021.02
    -
    2022.03

    Waseda University   Waseda Research Institute for Science and Engineering   Junior Researcher   Assistant Professor

  • 2016.04
    -
    2019.03

    Department of Applied Physics, Tokyo University of Science   Junior Associate Professor

  • 2011.04
    -
    2016.03

    Department of Applied Physics, Tokyo University of Science   Assistant Professor

  • 2010.04
    -
    2011.03

    Institute for Solid State Physics, University of Tokyo   JSPS Research Fellow (DC2)

Professional Memberships

  •  
     
     

    THE JAPANESE SOCIETY FOR SYNCHROTRON RADIATION RESEARCH

  •  
     
     

    THE PHYSICAL SOCIETY OF JAPAN

 

Research Areas

  • Magnetism, superconductivity and strongly correlated systems

  • Semiconductors, optical properties of condensed matter and atomic physics

Research Interests

  • strongly correlated electron system

  • photoemission spectroscopy

Papers

  • Valence Fluctuations in Yb(Al,Fe)B4 Studied by Nanosecond-time-resolved Photoemission Spectroscopy Using Synchrotron Radiation

    M. Okawa, K. Akikubo, S. Yamamoto, I. Matsuda, T. Saitoh

    e-Journal of Surface Science and Nanotechnology   19 ( 0 ) 20 - 23  2021.03  [Refereed]

    DOI

  • Electronic Structure of a Delafossite Oxide CuAlO2 in Comparison with CuCrO2

    Kenta Takahashi, Ryo Kato, Mario Okawa, Tetsuji Okuda, Akira Yasui, Eiji Ikenaga, Kanta Ono, Noriaki Hamada, Tomohiko Saitoh

    J PHYS SOC JPN   88   074701-1 - 074701-6  2019.06  [Refereed]

    DOI

  • Temperature-dependent valence state within the metallic phase of BaV10O15 probed by hard x-ray photoemission spectroscopy

    S. Dash, M. Okawa, T. Kajita, T. Yoshino, R. Shimoyama, K. Takahashi, Y. Takahashi, R. Takayanagi, T. Saitoh, A. Yasui, E. Ikenaga, N. L. Saini, T. Katsufuji, T. Mizokawa

    PHYS REV B   99   035122-1 - 035122-6  2019.01  [Refereed]

    DOI

  • Anomalous metallic state with strong charge fluctuations in BaxTi8 O16+δ revealed by hard x-ray photoemission spectroscopy

    S. Dash, T. Kajita, M. Okawa, T. Saitoh, E. Ikenaga, N. L. Saini, T. Katsufuji, T. Mizokawa

    Physical Review B   97 ( 16 ) 165116  2018.04  [Refereed]

     View Summary

    We have studied a charge-orbital driven metal-insulator transition (MIT) in hollandite-type BaxTi8O16+δ by means of hard x-ray photoemission spectroscopy (HAXPES). The Ti 2p HAXPES indicates strong Ti3+/Ti4+ charge fluctuation in the metallic phase above the MIT temperature. The metallic phase is characterized by a power-law spectral function near the Fermi level which would be a signature of bad metal with non-Drude polaronic behavior. The power-law spectral shape is associated with the large Seebeck coefficient of the metallic phase in BaxTi8O16+δ.

    DOI

  • Quantum valence criticality in a correlated metal

    Kentaro Kuga, Yosuke Matsumoto, Mario Okawa, Shintaro Suzuki, Takahiro Tomita, Keita Sone, Yasuyuki Shimura, Toshiro Sakakibara, Daisuke Nishio-Hamane, Yoshitomo Karaki, Yasutaka Takata, Masaharu Matsunami, Ritsuko Eguchi, Munetaka Taguchi, Ashish Chainani, Shik Shin, Kenji Tamasaku, Yoshinori Nishino, Makina Yabashi, Tetsuya Ishikawa, Satoru Nakatsuji

    Science Advances   4 ( 2 ) eaao3547  2018.02  [Refereed]

     View Summary

    A valence critical end point existing near the absolute zero provides a unique case for the study of a quantum version of the strong density fluctuation at the Widom line in the supercritical fluids. Although singular charge and orbital dynamics are suggested theoretically to alter the electronic structure significantly, breaking down the standard quasi-particle picture, this has never been confirmed experimentally to date. We provide the first empirical evidence that the proximity to quantum valence criticality leads to a clear breakdown of Fermi liquid behavior. Our detailed study of the mixed valence compound a-YbAlB4 reveals that a small chemical substitution induces a sharp valence crossover, accompanied by a pronounced non-Fermi liquid behavior characterized by a divergent effective mass and unusual T/B scaling in the magnetization.

    DOI PubMed

  • Observation of a pseudogap in the vicinity of the metal–insulator transition in the perovskite-type vanadium oxides Nd<inf>1−x</inf>Sr<inf>x</inf>VO<inf>3</inf>

    Shintaro Yamamoto, Daiki Ootsuki, Daiya Shimonaka, Daisuke Shibata, Kenjiro Kodera, Mario Okawa, Tomohiko Saitoh, Masafumi Horio, Atsushi Fujimori, Hiroshi Kumigashira, Kanta Ono, Eiji Ikenaga, Shigeki Miyasaka, Setsuko Tajima, Teppei Yoshida

    Journal of the Physical Society of Japan   87 ( 2 ) 024708  2018  [Refereed]

     View Summary

    © 2018 The Physical Society of Japan. We have performed a photoemission study of the Mott–Hubbard system Nd1−xSrxVO3 (x = 0.20 and 0.30) to investigate the electronic structure in the vicinity of the metal–insulator transition. By using bulk sensitive hard X-ray photoemission spectroscopy, we have observed a large coherent spectral weight near the Fermi level compared to those observed with surface-sensitive low photons. In particular, a pseudogap with an energy of ~0.2 eV has been observed near the Fermi level, which is consistent with a prediction with a dynamical cluster approximation calculation. In order to understand the characteristic features in the Mott–Hubbard-type metal–insulator transition, particularly the pseudogap opening at x = 0.2 and 0.3, a phenomenological model of the self-energy has been proposed.

    DOI

  • Electronic properties of Ba1-xSrxV13O18 (x=0,0.2,1) studied using hard x-ray photoelectron spectroscopy

    S. Dash, M. Okawa, T. Kajita, T. Yoshino, R. Shimoyama, K. Takahashi, Y. Takahashi, R. Takayanagi, T. Saitoh, D. Ootsuki, T. Yoshida, E. Ikenaga, N. L. Saini, T. Katsufuji, T. Mizokawa

    PHYSICAL REVIEW B   95 ( 19 ) 195116  2017.05  [Refereed]

     View Summary

    We have studied the electronic structure of Ba1-xSrxV13O18 (x = 0,0.2,1) at different temperatures across the trimerization and charge-order transitions using hard x-ray photoemission spectroscopy (HAXPES). The V 2p HAXPES indicates V2+/V3+ charge order and fluctuation in the high-temperature tetramer phase, low-temperature trimer phase, and intermediate-temperature charge-order phase in the series of x = 0,0.2,1. In the valence-band HAXPES, although the spectral weight at the Fermi level tends to be suppressed in all the phases due to strong charge order or fluctuation, it increases in the trimer phase at x = 0.2, in agreement with the decrease of resistivity and the increase of itinerant electrons in the trimer phase. Interestingly, in the most conducting x = 1 without the charge-order phase, the spectral weight at the Fermi level is strongly suppressed even in the trimer phase, indicating that charge fluctuation in the trimer phase is different between x = 0.2 and 1.

    DOI

  • Unusual valence state and metal-insulator transition in BaV10 O-15 probed by hard x-ray photoemission spectroscopy

    T. Yoshino, M. Okawa, T. Kajita, S. Dash, R. Shimoyama, K. Takahashi, Y. Takahashi, R. Takayanagi, T. Saitoh, D. Ootsuki, T. Yoshida, E. Ikenaga, N. L. Saini, T. Katsufuji, T. Mizokawa

    PHYSICAL REVIEW B   95 ( 7 ) 075151  2017.02  [Refereed]

     View Summary

    We have studied the electronic structure of BaV10O15 across the metal-insulator transition with V trimerization by means of hard-x-ray photoemission spectroscopy (HAXPES) and mean-field calculations. The V 2p HAXPES indicates V2.5+-V3+ charge fluctuation in the metallic phase, and V2+-V3+ charge order in the insulating phase. The V2.5+-V3+ charge fluctuation is consistent with the mean-field solution where a V 3d a(1g) electron is shared by two V sites with face-sharing VO6 octahedra. The valence- band HAXPES of the metallic phase exhibits pseudogap opening at the Fermi level associated with the charge fluctuation, and a band gap similar to 200 meV is established in the insulating phase due to the switching of charge correlation.

    DOI

  • Coexistence of a pseudogap and a superconducting gap for the high-Tc superconductor La2-xSrxCuO4 studied by angle-resolved photoemission spectroscopy

    T. Yoshida, W. Malaeb, S. Ideta, D. H. Lu, R. G. Moor, Z. X. Shen, M. Okawa, T. Kiss, K. Ishizaka, S. Shin, Seiki Komiya, Yoichi Ando, H. Eisaki, S. Uchida, A. Fujimori

    Physical Review B   93 ( 1 )  2016.01  [Refereed]

     View Summary

    The relationship between the superconducting gap and the pseudogap has been the subject of controversies. In order to clarify this issue, we have studied the superconducting gap and pseudogap of the high-Tc superconductor La2-xSrxCuO4 (x=0.10,14) by angle-resolved photoemission spectroscopy (ARPES). Through the analysis of the ARPES spectra above and below Tc, we have identified a superconducting coherence peak even in the antinodal region on top of the pseudogap of a larger energy scale. The superconducting peak energy nearly follows the pure d-wave form. The d-wave order parameter Δ0 [defined by Δ(k)=Δ0(coskxa-coskya)] for x=0.10 and 0.14 are nearly the same, Δ0∼12-14meV, leading to strong coupling 2Δ0/kBTc∼10. The present result indicates that the pseudogap and the superconducting gap are distinct phenomena and can be described by the "two-gap" scenario.

    DOI

  • Ce Core-Level Spectroscopy, and Magnetic and Electrical Transport Properties of Lightly Ce-Doped YCoO3

    Kobayashi, Yoshihiko, Koike, Tsuyoshi, Okawa, Mario, Takayanagi, Ryohei, Takei, Shohei, Minohara, Makoto, Kobayashi, Masaki, Horiba, Koji, Kumigashira, Hiroshi, Yasui, Akira, Ikenaga, Eiji, Saitoh, Tomohiko, Asai, Kichizo

    Journal of the Physical Society of Japan   85 ( 11 ) 114704  2016  [Refereed]

    DOI

  • Hybridization gap formation in the Kondo insulator YbB12 observed using time-resolved photoemission spectroscopy

    M. Okawa, Y. Ishida, M. Takahashi, T. Shimada, F. Iga, T. Takabatake, T. Saitoh, S. Shin

    Physical Review B - Condensed Matter and Materials Physics   92 ( 16 )  2015.10  [Refereed]

     View Summary

    A detailed low-energy electronic structure of a Kondo insulator YbB12 was revealed by a synergetic combination of ultra-high-resolution laser photoemission spectroscopy (PES) and time-resolved PES. The former confirmed a 25-meV pseudogap corresponding to the Kondo temperature of this material, and more importantly, it revealed that a 15-meV gap and a Kondo-peak feature developed below a crossover temperature of T∗∼110K. In harmony with this, the latter discovered a very long recombination time exceeding 100 ps below ∼T∗. This is a clear manifestation of photoexcited carriers due to the bottleneck in the recovery dynamics, which is interpreted as a developing hybridization gap of a hard gap.

    DOI

  • Electronic Structure Evolution across the Peierls Metal-Insulator Transition in a Correlated Ferromagnet

    P. A. Bhobe, A. Kumar, M. Taguchi, R. Eguchi, M. Matsunami, Y. Takata, A. K. Nandy, P. Mahadevan, D. D. Sarma, A. Neroni, E. Sasioglu, M. Lezaic, M. Oura, Y. Senba, H. Ohashi, K. Ishizaka, M. Okawa, S. Shin, K. Tamasaku, Y. Kohmura, M. Yabashi, T. Ishikawa, K. Hasegawa, M. Isobe, Y. Ueda, A. Chainani

    PHYSICAL REVIEW X   5 ( 4 ) 041004  2015.10  [Refereed]

     View Summary

    Transition metal compounds often undergo spin-charge-orbital ordering due to strong electron-electron correlations. In contrast, low-dimensional materials can exhibit a Peierls transition arising from low-energy electron-phonon-coupling-induced structural instabilities. We study the electronic structure of the tunnel framework compound K2Cr8O16, which exhibits a temperature-dependent (T-dependent) paramagnetic-to-ferromagnetic- metal transition at T-C = 180 K and transforms into a ferromagnetic insulator below T-MI = 95 K. We observe clear T-dependent dynamic valence (charge) fluctuations from above T-C to T-MI, which effectively get pinned to an average nominal valence of Cr+3.75 (Cr4+:Cr3+ states in a 3:1 ratio) in the ferromagnetic-insulating phase. High-resolution laser photoemission shows a T-dependent BCS-type energy gap, with 2G(0) similar to 3.5(k(B)T(MI)) similar to 35 meV. First-principles band-structure calculations, using the experimentally estimated on-site Coulomb energy of U similar to 4 eV, establish the necessity of strong correlations and finite structural distortions for driving the metal-insulator transition. In spite of the strong correlations, the nonintegral occupancy (2.25 d-electrons/Cr) and the half-metallic ferromagnetism in the t(2g) up-spin band favor a low-energy Peierls metal-insulator transition.

    DOI

  • Nonequilibrium electronic and phonon dynamics of Cu0.17Bi2Se3 investigated by core-level and valence-band time-resolved photoemission spectroscopy

    T. Yamamoto, Y. Ishida, R. Yoshida, M. Okawa, K. Okazaki, T. Kanai, A. Kikkawa, Y. Taguchi, T. Kiss, K. Ishizaka, N. Ishii, J. Itatani, S. Watanabe, Y. Tokura, T. Saitoh, S. Shin

    PHYSICAL REVIEW B   92 ( 12 ) 121106(R)  2015.09  [Refereed]

     View Summary

    We have performed time-resolved (TR) core-level and valence-band angle-resolved (AR) photoemission spectroscopy (PES) to investigate ultrafast dynamics of an electron-doped topological insulator Cu0.17Bi2Se3. The Bi 5d(5/2) line was composed of a single peak and exhibited broadening upon both heating and pumping, which we interpreted as a change of phonon temperature (T-p), in the surface region. The electronic dynamics and electron temperature (T-e), on the other hand, were determined with near-E-F TRARPES. The transient temperature deduced from core-level TRPES shows a similar behavior with T-e deduced from near-E-F TRARPES. This similar behavior of T-p and T-e can be reproduced not by a simple two-temperature model but by a modified one, although we cannot exclude a possibility that core-level broadening also reflects T-e.

    DOI

  • Laboratory hard X-ray photoelectron spectroscopy of La1-xSrxMnO3

    Tomoko Hishida, Masaaki Kobata, Eiji Ikenaga, Takeharu Sugiyama, Kazushige Ohbayashi, Keisuke Kobayashi, Mario Okawa, Tomohiko Saitoh

    JAPANESE JOURNAL OF APPLIED PHYSICS   54 ( 8 ) 083201  2015.08  [Refereed]

     View Summary

    A laboratory hard X-ray photoelectron spectroscopy (HXPS) system equipped with a monochromatic Cr K alpha (hv = 5414.7 eV) X-ray source was applied to an investigation of the core-level electronic structure of La1-xSrxMnO3. No appreciable high binding-energy shoulder in the O 1s HXPS spectra were observed while an enhanced low binding-energy shoulder structure in the Mn 2p(3/2) HXPS spectra were observed, both of which are manifestation of high bulk sensitivity. Such high bulk sensitivity enabled us to track the Mn 2p(3/2) shoulder structure in the full range of x, giving us a new insight into the binding-energy shift of the Mn 2p(3/2) core level. Comparisons with the results using the conventional laboratory XPS (hv = 1486.6 eV) as well as those using a synchrotron radiation source (hv = 7939.9 eV) demonstrate that HXPS is a powerful and convenient tool to analyze the bulk electronic structure of a host of different compounds. (C) 2015 The Japan Society of Applied Physics

    DOI

  • Emergent photovoltage on SmB6 surface upon bulk-gap evolution revealed by pump-and-probe photoemission spectroscopy

    Y. Ishida, T. Otsu, T. Shimada, M. Okawa, Y. Kobayashi, F. Iga, Y. Takabatake, S. Shin

    SCIENTIFIC REPORTS   5   8160  2015.02  [Refereed]

     View Summary

    Recent studies suggest that an exemplary Kondo insulator SmB6 belongs to a new class of topological insulators (TIs), in which non-trivial spin-polarized metallic states emerge on surface upon the formation of Kondo hybridization gap in the bulk. Remarkably, the bulk resistivity reaches more than 20 Omega cm at 4 K, making SmB6 a candidate for a so-called bulk-insulating TI. We here investigate optical-pulse responses of SmB6 by pump-and-probe photoemission spectroscopy. Surface photovoltage effect is observed below similar to 90 K. This indicates that an optically-active band bending region develops beneath the novel metallic surface upon the bulk-gap evolution. The photovoltaic effect persists for &gt;200 mu s, which is long enough to be detected by electronics devices, and could be utilized for optical gating of the novel metallic surface.

    DOI

  • Cu–O–Cr Hybridization Effects on the Electronic Structure of a Hole-Doped Delafossite Oxide CuCr1−xMgxO2

    M. Okawa, T. Yokobori, K. Konishi, R. Takei, K. Katayama, S. Oozono, T. Shinmura, T. Okuda, H. Wadati, E. Sakai, K. Ono, H. Kumigashira, M. Oshima, T. Sugiyama, E. Ikenaga, N. Hamada, T. Saitoh

    JPS Conference Proceedings   3   017027  2014.06  [Refereed]

    DOI

  • Electronic Structure Evolution of La0.6Sr0.4Mn1−yNbyO3 across a Metal-Insulator Transition by Nb Doping

    T. Hishida, K. Ohbayashi, M. Okawa, T. Saitoh

    JPS Conference Proceedings   3   013022  2014.06  [Refereed]

    DOI

  • Growth of TiO2-delta thin film by RF magnetron sputtering using oxygen radicals and Ti metal

    Yuichi Shimazu, Teppei Okumura, Enju Sakai, Hiroshi Kumigashira, Mario Okawa, Tomohiko Saitoh, Tohru Higuchi

    JAPANESE JOURNAL OF APPLIED PHYSICS   53 ( 6 ) 06JG01  2014.06  [Refereed]

     View Summary

    TiO2-delta thin films have been deposited by RF magnetron sputtering using oxygen radicals. The deposition rate of the thin films largely increases with oxygen radical irradiation during the deposition in the metal mode. A as-deposited TiO2-delta thin film on a Pt substrate prepared at the substrate temperature of 300 degrees C crystallizes without postannealing. The Ti 2p X-ray absorption spectrum indicates that the Ti 3d electron enters the bottom of the conduction band. The Ti 3d states at the Fermi level (E-F) and at similar to 1.5 eV from E-F in the band gap energy region are closely related to the electrical conductivity. (C) 2014 The Japan Society of Applied Physics

    DOI

  • A self-emissivity-controlling radiator for spacecrafts by making use of a metal-insulator transition in magnetoresistive manganites

    Kohsuke Tanaka, Sumitaka Tachikawa, Hideki Kuwahara, Mario Okawa, Tomohiko Saitoh

    JPS Conference Proceedings   1   012005  2014.03  [Refereed]

    DOI

  • Buried well-screened state in photoemission spectra of La1-xSrxMnO3

    Tomoko Hishida, Kazusige Ohbayashi, Masaaki Kobata, Eiji Ikenaga, Takeharu Sugiyama, Keisuke Kobayashi, Mario Okawa, Tomohiko Saitoh

    JPS Conference Proceedings   1   012109  2014.03  [Refereed]

    DOI

  • Empirical relationship between x-ray photoemission spectra and electrical conductivity in a colossal magnetoresistive manganite La1-xSrxMnO3

    T. Hishida, K. Ohbayashi, M. Kobata, E. Ikenaga, T. Sugiyama, K. Kobayashi, M. Okawa, T. Saitoh

    JOURNAL OF APPLIED PHYSICS   113 ( 23 ) 233702  2013.06  [Refereed]

     View Summary

    By using laboratory x-ray photoemission spectroscopy (XPS) and hard x-ray photoemission spectroscopy (HX-PES) at a synchrotron facility, we report an empirical semi-quantitative relationship between the valence/core-level x-ray photoemission spectral weight and electrical conductivity in La1-xSrxMnO3 as a function of x. In the Mn 2p(3/2) HX-PES spectra, we observed the shoulder structure due to the Mn3+ well-screened state. However, the intensity at x = 0.8 was too small to explain its higher electrical conductivity than x = 0.0, which confirms our recent analysis on the Mn 2p(3/2) XPS spectra. The near-Fermi level XPS spectral weight was found to be a measure of the variation of electrical conductivity with x in spite of a far lower energy resolution compared with the energy scale of the quasiparticle (coherent) peak because of the concurrent change of the coherent and incoherent spectral weight. (C) 2013 AIP Publishing LLC.

    DOI

  • Electronic structure of the hole-doped delafossite oxides CuCr <inf>1-x</inf>Mg<inf>x</inf>O<inf>2</inf>

    T. Yokobori, M. Okawa, K. Konishi, R. Takei, K. Katayama, S. Oozono, T. Shinmura, T. Okuda, H. Wadati, E. Sakai, K. Ono, H. Kumigashira, M. Oshima, T. Sugiyama, E. Ikenaga, N. Hamada, T. Saitoh

    Physical Review B - Condensed Matter and Materials Physics   87 ( 19 )  2013.05

     View Summary

    We report the detailed electronic structure of a hole-doped delafossite oxide CuCr1-xMgxO2 (0≤x≤0.03) studied by photoemission spectroscopy (PES), soft x-ray absorption spectroscopy (XAS), and band-structure calculations within the local-density approximation +U (LDA+U) scheme. Cr/Cu 3p-3d resonant PES reveals that the near-Fermi-level leading structure has primarily the Cr 3d character with a minor contribution from the Cu 3d through Cu 3d-O 2p-Cr 3d hybridization, having good agreement with the band-structure calculations. This indicates that a doped hole will have primarily the Cr 3d character. Cr 2p PES and L-edge XAS spectra exhibit typical Cr3+ features for all x, while the Cu L-edge XAS spectra exhibited a systematic change with x. This indicates now that the Cu valence is monovalent at x=0 and the doped hole should have Cu 3d character. Nevertheless, we surprisingly observed two types of charge-transfer satellites that should be attributed to Cu+ (3d10) and Cu2+ (3d9) like initial states in Cu 2p-3d resonant PES spectrum of at x=0, while Cu 2p PES spectra with no doubt shows the Cu+ character even for the lightly doped samples. We propose that these contradictory results can be understood by introducing not only the Cu 4s state, but also finite Cu 3d,4s-Cr 3d charge transfer via O 2p states in the ground-state electronic configuration. © 2013 American Physical Society.

    DOI

  • Electronic structure of the hole-doped delafossite oxides CuCr1-xMgxO2

    T. Yokobori, M. Okawa, K. Konishi, R. Takei, K. Katayama, S. Oozono, T. Shinmura, T. Okuda, H. Wadati, E. Sakai, K. Ono, H. Kumigashira, M. Oshima, T. Sugiyama, E. Ikenaga, N. Hamada, T. Saitoh

    PHYSICAL REVIEW B   87 ( 19 ) 195124  2013.05  [Refereed]

     View Summary

    We report the detailed electronic structure of a hole-doped delafossite oxide CuCr1-xMgxO2 (0 &lt;= x &lt;= 0.03) studied by photoemission spectroscopy (PES), soft x-ray absorption spectroscopy (XAS), and band-structure calculations within the local-density approximation + U (LDA + U) scheme. Cr/Cu 3p-3d resonant PES reveals that the near-Fermi-level leading structure has primarily the Cr 3d character with a minor contribution from the Cu 3d through Cu 3d-O 2p-Cr 3d hybridization, having good agreement with the band-structure calculations. This indicates that a doped hole will have primarily the Cr 3d character. Cr 2p PES and L-edge XAS spectra exhibit typical Cr3+ features for all x, while the Cu L-edge XAS spectra exhibited a systematic change with x. This indicates now that the Cu valence is monovalent at x = 0 and the doped hole should have Cu 3d character. Nevertheless, we surprisingly observed two types of charge-transfer satellites that should be attributed to Cu+ (3d(10)) and Cu2+ (3d(9)) like initial states in Cu 2p-3d resonant PES spectrum of at x = 0, while Cu 2p PES spectra with no doubt shows the Cu+ character even for the lightly doped samples. We propose that these contradictory results can be understood by introducing not only the Cu 4s state, but also finite Cu 3d, 4s-Cr 3d charge transfer via O 2p states in the ground-state electronic configuration.

    DOI

  • Effects of hole-doping and disorder on the magnetic states of delafossite CuCrO2 having a spin-3/2 antiferromagnetic triangular sublattice

    Tetsuji Okuda, Ryoichi Kajimoto, Mario Okawa, Tomohiko Saitoh

    International Journal of Modern Physics B   27 ( 5 ) 1330002  2013.02  [Refereed]  [Invited]

     View Summary

    In this review, we will discuss the effects of itinerant hole and disorder produced by substitutions on the magnetic states of polycrystalline delafossite oxide CuCrO2 having a spin-3/2 antiferromagnetic triangular sublattice. First, we will show the effects of hole-doping by the substitution of nonmagnetic Mg2+ for magnetic Cr3+ on the physical properties of CuCrO2, and will discuss the origin of nontrivial promotion of the 120° Néel state due to the coupling between the itinerant hole and localized spin. Next, we will show the effects of disorder introduced by the isovalent substitutions such as the nonmagnetic Ag+ substitution for nonmagnetic Cu+ and the nonmagnetic Al3+ one for magnetic Cr3+, and will discuss the possibility of appearance of unusual magnetic states such as spin liquid or spin nematic states. © 2013 World Scientific Publishing Company.

    DOI

  • Bulk-Sensitive Angle-Resolved Photoemission Spectroscopy on TTF-TCNQ

    Kenji Koizumi, Kyoko Ishizaka, Takayuki Kiss, Mario Okawa, Reizo Kato, Shik Shin

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   82 ( 2 ) 025004  2013.02  [Refereed]

    DOI

  • Observation of two fine structures related to the hidden order in the spectral functions of URu 2Si 2

    Rikiya Yoshida, Masaki Fukui, Yoshinori Haga, Etsuji Yamamoto, Yoshichika Onuki, Mario Okawa, Walid Malaeb, Shik Shin, Yuji Muraoka, Takayoshi Yokoya

    Physical Review B - Condensed Matter and Materials Physics   85 ( 24 ) 241102  2012.06  [Refereed]

     View Summary

    We studied the spectral functions of URu 2Si 2 in the hidden-order state by means of ultrahigh-resolution angle-resolved photoemission spectroscopy. High signal-to-noise ratio data uncover the existence of two anomalous fine structures, namely a "splitting" in the previously reported narrow dispersive band, and a small, dispersionless "satellite" structure. These structures can be explained by neither ordinary bands nor the development of a hybridization of two states
    thus our observation should evoke the consideration of complicated many-body effects. As a possible origin, we suggest the existence of electron-mode coupling in the ordered state. © 2012 American Physical Society.

    DOI

  • Angle-resolved photoemission study on the superconducting iron-pnictides of BaFe2(As, P)(2) with low energy photons

    T. Shimojima, F. Sakaguchi, K. Ishizaka, Y. Ishida, W. Malaeb, T. Yoshida, S. Ideta, A. Fujimori, T. Kiss, M. Okawa, T. Togashi, C. -T. Chen, S. Watanabe, Y. Nakashima, A. Ino, H. Anzai, M. Arita, K. Shimada, H. Namatame, M. Taniguchi, S. Kasahara, T. Terashima, T. Shibauchi, Y. Matsuda, M. Nakajima, S. Uchida, K. Kihou, C. H. Lee, A. Iyo, H. Eisaki, A. Chainani, S. Shin

    SOLID STATE COMMUNICATIONS   152 ( 8 ) 695 - 700  2012.04  [Refereed]

     View Summary

    We investigate the k(z) dispersion in the hole Fermi surfaces (FSs) and the superconducting (SC) gaps of BaFe2(As0.65P0.35)(2) by employing bulk-sensitive angle-resolved photoemission spectroscopy (ARPES) with low energy photons. We find that this material exhibits a comparable magnitude of SC gaps for three-hole FSs at k(z) similar to pi. The comparable magnitude of the SC gap is observed also at k(z) similar to 0. Since each FS sheet has a distinct orbital character, these observations are an indication of the orbital-independent SC gaps in the hole FSs. (C) 2011 Elsevier Ltd. All rights reserved.

    DOI

  • Common Origin of the Circular-Dichroism Pattern in Angle-Resolved Photoemission Spectroscopy of SrTiO3 and CuxBi2Se3

    Y. Ishida, H. Kanto, A. Kikkawa, Y. Taguchi, Y. Ito, Y. Ota, K. Okazaki, W. Malaeb, M. Mulazzi, M. Okawa, S. Watanabe, C. -T. Chen, M. Kim, C. Bell, Y. Kozuka, H. Y. Hwang, Y. Tokura, S. Shin

    PHYSICAL REVIEW LETTERS   107 ( 7 ) 077601  2011.08  [Refereed]

     View Summary

    Circular dichroism in the angular distribution of photoelectrons from SrTiO3: Nb and CuxBi2Se3 is investigated by 7-eV laser angle-resolved photoemission spectroscopy. In addition to the well-known node that occurs in the circular dichroism pattern when the incidence plane matches the mirror plane of the crystal, we show that another type of node occurs when the mirror plane of the crystal is vertical to the incidence plane and the electronic state is two-dimensional. The flower-shaped circular dichroism patterns in the angular distribution occurring around the Fermi level of SrTiO3: Nb and around the Dirac point of CuxBi2Se3 are explained on equal footings. We point out that the penetration depth of the topological states of CuxBi2Se3 depends on momentum.

    DOI PubMed

  • Ultrahigh-resolution laser photoemission study of URu2Si2 across the hidden-order transition

    Rikiya Yoshida, Yoshiaki Nakamura, Masaki Fukui, Yoshinori Haga, Etsuji Yamamoto, Yoshichika Onuki, Mario Okawa, Shik Shin, Masaaki Hirai, Yuji Muraoka, Takayoshi Yokoya

    JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS   72 ( 5 ) 580 - 581  2011.05  [Refereed]

     View Summary

    We have studied the electronic structures of URu2Si2 employing ultrahigh-resolution laser angle-resolved photoemission spectroscopy. The change of photoemission spectra is investigated across the hidden-order transition, and the emergence of a narrow band is clearly observed near the Fermi level for both (pi,0) and (pi,pi) directions. In addition, it is shown that tuning of light&apos;s polarization allows the signal of a hole-like dispersive feature to enhance. These observations prove that laser angle-resolved photoemission spectroscopy is an effective tool for studying the evolution of electronic structures across the hidden-order transition in URu2Si2. (C) 2010 Elsevier Ltd. All rights reserved.

    DOI

  • Two-Fermi-Surface Superconducting State and a Nodal d-Wave Energy Gap of the Electron-Doped Sm1.85Ce0.15CuO4-delta Cuprate Superconductor

    A. F. Santander-Syro, M. Ikeda, T. Yoshida, A. Fujimori, K. Ishizaka, M. Okawa, S. Shin, R. L. Greene, N. Bontemps

    PHYSICAL REVIEW LETTERS   106 ( 19 ) 197002  2011.05  [Refereed]

     View Summary

    We report on laser-excited angle-resolved photoemission spectroscopy in the electron-doped cuprate Sm1.85Ce0.15CuO4-delta. The data show the existence of a nodal hole-pocket Fermi surface both in the normal and superconducting states. We prove that its origin is long-range antiferromagnetism by an analysis of the coherence factors in the main and folded bands. This coexistence of long-range antiferrmagnetism and superconductivity implies that electron-doped cuprates are two-Fermi-surface superconductors. The measured superconducting gap in the nodal hole pocket is compatible with a d-wave symmetry.

    DOI

  • Orbital-Independent Superconducting Gaps in Iron Pnictides

    T. Shimojima, F. Sakaguchi, K. Ishizaka, Y. Ishida, T. Kiss, M. Okawa, T. Togashi, C. -T. Chen, S. Watanabe, M. Arita, K. Shimada, H. Namatame, M. Taniguchi, K. Ohgushi, S. Kasahara, T. Terashima, T. Shibauchi, Y. Matsuda, A. Chainani, S. Shin

    SCIENCE   332 ( 6029 ) 564 - 567  2011.04  [Refereed]

     View Summary

    The origin of superconductivity in the iron pnictides has been attributed to antiferromagnetic spin ordering that occurs in close combination with a structural transition, but there are also proposals that link superconductivity to orbital ordering. We used bulk-sensitive laser angle-resolved photoemission spectroscopy on BaFe2(As0.65P0.35)(2) and Ba0.6K0.4Fe2As2 to elucidate the role of orbital degrees of freedom on the electron-pairing mechanism. In strong contrast to previous studies, an orbital-independent superconducting gap magnitude was found for the hole Fermi surfaces. Our result is not expected from the superconductivity associated with spin fluctuations and nesting, but it could be better explained invoking magnetism-induced interorbital pairing, orbital fluctuations, or a combination of orbital and spin fluctuations. Regardless of the interpretation, our results impose severe constraints on theories of iron pnictides.

    DOI PubMed

  • Electronic structure of an antiferromagnetic metal: CaCrO3

    P. A. Bhobe, A. Chainani, M. Taguchi, R. Eguchi, M. Matsunami, T. Ohtsuki, K. Ishizaka, M. Okawa, M. Oura, Y. Senba, H. Ohashi, M. Isobe, Y. Ueda, S. Shin

    PHYSICAL REVIEW B   83 ( 16 ) 165132  2011.04  [Refereed]

     View Summary

    We report on the electronic structure of the perovskite oxide CaCrO3 using valence-band, core-level, and Cr 2p-3d resonant photoemission spectroscopy (PES). Despite its antiferromagnetic order, a clear Fermi edge characteristic of a metal with dominant Cr 3d character is observed in the valence-band spectrum. The Cr 3d single-particle density of states are spread over 2 eV, with the photoemission spectral weight distributed in two peaks centered at similar to 1.2 and 0.2 eV below E-F, suggestive of the coherent and incoherent states resulting from strong electron-electron correlations. Resonant PES across the Cr 2p-3d threshold identifies a "two-hole" correlation satellite and yields an on-site Coulomb energy U similar to 4.8 eV. The metallic DOS at E-F is also reflected through the presence of a well-screened feature at the low binding energy side of the Cr 2p core-level spectrum. X-ray-absorption spectroscopy at Cr L-3,L-2 and O K edges exhibit small temperature-dependent changes that point toward a small change in Cr-O hybridization. The Cr 2p core-level spectrum can be reproduced using cluster model calculations that include a charge transfer from the metallic screening channel at E-F. The overall results indicate that CaCrO3 is a strongly hybridized antiferromagnetic metal, lying in the regime intermediate to Mott-Hubbard and charge-transfer systems.

    DOI

  • Three energy scales characterizing the competing pseudogap state, the incoherent, and the coherent superconducting state in high-T-c cuprates

    Y. Okada, T. Kawaguchi, M. Ohkawa, K. Ishizaka, T. Takeuchi, S. Shin, H. Ikuta

    PHYSICAL REVIEW B   83 ( 10 ) 104502  2011.03  [Refereed]

     View Summary

    We have studied the momentum dependence of the energy gap of Bi-2(Sr, R)(2)CuOy by angle-resolved photoemission spectroscopy (ARPES), particularly focusing on the difference between R = La and Eu. By comparing the gap function and characteristic temperatures between the two sets of samples, we show that there exist three distinct energy scales, Delta(pg), Delta(sc0), and Delta(eff)(sc0), which correspond to T* (pseudogap temperature), T-onset (onset temperature of fluctuating superconductivity), and T-c (critical temperature of coherent superconductivity). The results not only support the existence of a pseudogap state below T* that competes with superconductivity, but also the duality of competition and superconducting fluctuation at momenta around the antinode below T-onset.

    DOI

  • Coexistence of antiferromagnetism and superconductivity in the electron-doped cuprate Sm1.85Ce0.15CuO4-d

    A. F. Santander-Syro, M. Ikeda, T. Yoshida, A. Fujimori, K. Ishizaka, M. Okawa, S. Shin, R.L. Greene, N. Bontemps

    Phys. Rev. Lett. 106, 197002 (2011).    2011  [Refereed]

    DOI

  • Electronic structure of U(Ru1-xRhx)(2)Si-2 studied by laser angle-resolved photoemission spectroscopy

    Yoshida R, Nakamura Y, Fukui M, Haga Y, Yamamoto E, Onuki Y, Okawa M, Shin S, Hirai M, Muraoka Y, Yokoya T

    INTERNATIONAL CONFERENCE ON STRONGLY CORRELATED ELECTRON SYSTEMS (SCES 2010)   273  2011  [Refereed]

    DOI

  • Bulk-sensitive laser-ARPES study on the cuprate superconductor YBa2Cu3O7-delta

    M. Okawa, K. Ishizaka, H. Uchiyama, H. Tadatomo, T. Masui, S. Tajima, X-Y. Wang, C-T. Chen, S. Watanabe, A. Chainani, T. Saitoh, S. Shin

    PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS   470   S62 - S64  2010.12  [Refereed]

     View Summary

    We investigate the bulk superconducting electronic structure in optimally doped YBa2Cu3O7-delta (YBCO) using laser-excited angle-resolved photoemission spectroscopy. The band dispersions with the d(x2-y2)-wave like gap opening are observed without being hindered by surface state and CuO chain band due to bulk-sensitivity and/or matrix element effect at hv = 6.994 eV. The momentum-dependence of the superconducting gap exhibits a nonzero minimum of similar to 12 meV along the (0,0) (pi,pi) line. In addition, the unusual suppression of the quasiparticle coherence is observed at T/T-c &gt; 0.5-0.7. (C) 2009 Elsevier B.V. All rights reserved.

    DOI

  • Analysis on photoemission spectrum of superconducting FeSe

    Rikiya Yoshida, Takanori Wakita, Hiroyuki Okazaki, Yoshikazu Mizuguchi, Shunsuke Tsuda, Yoshihiko Takano, Hiroyuki Takeya, Kazuto Hirata, Yukako Kato, Takayuki Muro, Mario Okawa, Kyoko Ishizaka, Shik Shin, Hisatomo Harima, Masaaki Hirai, Yuji Muraoka, Takayoshi Yokoya

    PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS   470   S389 - S390  2010.12  [Refereed]

     View Summary

    In this paper, we present the result of soft X-ray photoemission spectroscopy and its comparison with the density functional calculation. Although local density approximation seems to be a good starting point for describing the electronic structure of FeSe, the simulated spectrum poorly reproduced the structure around E-B = 2 eV. This result suggests the necessity of theoretical treatment beyond local density approximation. (C) 2009 Elsevier B.V. All rights reserved.

    DOI

  • Signature of hidden order and evidence for periodicity modification in URu2Si2

    Rikiya Yoshida, Yoshiaki Nakamura, Masaki Fukui, Yoshinori Haga, Etsuji Yamamoto, Yoshichika Onuki, Mario Okawa, Shik Shin, Masaaki Hirai, Yuji Muraoka, Takayoshi Yokoya

    PHYSICAL REVIEW B   82 ( 20 ) 205108  2010.11  [Refereed]

     View Summary

    The detail of electronic structures near the Fermi level in URu2Si2 has been investigated employing state-of-art laser angle-resolved photoemission spectroscopy. The observation of a narrow dispersive band near the Fermi level in the ordered state as well as its absence in a Rh-substituted sample strongly suggest that the emergence of the narrow band is a clear signature of the hidden-order transition. The temperature dependence of the narrow band, which appears at the onset of the hidden-order transition, invokes the occurrence of periodicity modification in the ordered state, which is shown for the first time by any spectroscopic probe. We compare our data to other previous studies and discuss possible implications.

    DOI

  • Strong Valence Fluctuation in the Quantum Critical Heavy Fermion Superconductor beta-YbAlB4: A Hard X-Ray Photoemission Study

    M. Okawa, M. Matsunami, K. Ishizaka, R. Eguchi, M. Taguchi, A. Chainani, Y. Takata, M. Yabashi, K. Tamasaku, Y. Nishino, T. Ishikawa, K. Kuga, N. Horie, S. Nakatsuji, S. Shin

    PHYSICAL REVIEW LETTERS   104 ( 24 ) 247201  2010.06  [Refereed]

     View Summary

    Electronic structures of the quantum critical superconductor beta-YbAlB4 and its polymorph alpha-YbAlB4 are investigated by using bulk-sensitive hard x-ray photoemission spectroscopy. From the Yb 3d core level spectra, the values of the Yb valence are estimated to be similar to 2.73 and similar to 2.75 for alpha- and beta-YbAlB4, respectively, thus providing clear evidence for valence fluctuations. The valence band spectra of these compounds also show Yb2+ peaks at the Fermi level. These observations establish an unambiguous case of a strong mixed valence at quantum criticality for the first time among heavy fermion systems, calling for a novel scheme for a quantum critical model beyond the conventional Doniach picture in beta-YbAlB4.

    DOI

  • Orbital-Dependent Modifications of Electronic Structure across the Magnetostructural Transition in BaFe2As2

    T. Shimojima, K. Ishizaka, Y. Ishida, N. Katayama, K. Ohgushi, T. Kiss, M. Okawa, T. Togashi, X. -Y. Wang, C. -T. Chen, S. Watanabe, R. Kadota, T. Oguchi, A. Chainani, S. Shin

    PHYSICAL REVIEW LETTERS   104 ( 5 ) 57002  2010.02  [Refereed]

     View Summary

    Laser angle-resolved photoemission spectroscopy (ARPES) is employed to investigate the temperature (T) dependence of the electronic structure in BaFe2As2 across the magnetostructural transition at T-N similar to 140 K. A drastic transformation in Fermi surface (FS) shape across T-N is observed, as expected by first-principles band calculations. Polarization-dependent ARPES and band calculations consistently indicate that the observed FSs at k(z) similar to pi in the low-T antiferromagnetic state are dominated by the Fe3d(zx) orbital, leading to the twofold electronic structure. These results indicate that magnetostructural transition in BaFe2As2 accompanies orbital-dependent modifications in the electronic structure.

    DOI

  • Bulk-sensitive spectroscopic studies on noncentrosymmetric superconducting system of Mg-Ir-B

    R. Yoshida, H. Okazaki, K. Iwai, K. Noami, T. Muro, M. Okawa, K. Ishizaka, S. Shin, Z. Li, J. L. Luo, G. -Q. Zheng, T. Oguchi, M. Hirai, Y. Muraoka, T. Yokoya

    PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS   469 ( 15-20 ) 1034 - 1036  2009.08  [Refereed]

     View Summary

    We present the data from ultrahigh-resolution laser-excited photoemission spectroscopy on a newly discovered noncentrosymmetric superconcluctor Mg(10)Ir(19)B(16). We observed the evidences for the opening of superconducting gap where numerical fittings show that isotropic s-wave model can satisfactorily explain the behavior of spectra near the Fermi level. We also present the valence band photoemission spectrum and B K fluorescence spectrum to discuss the basic electronic structure of Mg(10)Ir(19)B(16). (C) 2009 Elsevier B.V. All rights reserved.

    DOI

  • Superconducting electronic state in optimally doped YBa2Cu3O7-delta observed with laser-excited angle-resolved photoemission spectroscopy

    M. Okawa, K. Ishizaka, H. Uchiyama, H. Tadatomo, T. Masui, S. Tajima, X. -Y. Wang, C. -T. Chen, S. Watanabe, A. Chainani, T. Saitoh, S. Shin

    PHYSICAL REVIEW B   79 ( 14 ) 144528  2009.04  [Refereed]

     View Summary

    Low-energy electronic structure of optimally doped YBa2Cu3O7-delta is investigated using laser-excited angle-resolved photoemission spectroscopy. The surface state and the CuO chain band that usually overlap the CuO2 plane derived bands are not detected, thus enabling a clear observation of the bulk superconducting state. The observed bilayer splitting of the Fermi surface is similar to 0.08 A(-1) along (0,0)-(pi,pi) direction, significantly larger than Bi2Sr2CaCu2O8+delta. The kink structure of the band dispersion reflecting the renormalization effect at similar to 60 meV shows up similarly as in other hole-doped cuprates. The momentum dependence of the superconducting gap shows d(x)(2)-y(2)-wave-like amplitude but exhibits a nonzero minimum of similar to 12 meV along the (0,0)-(pi,pi) direction. Possible origins of such an unexpected "nodeless" gap behavior are discussed.

    DOI

  • Superconducting Gap and Valence Band of Mg10Ir19B16 Studied by Laser and Synchrotron Photoemission Spectroscopy

    Rikiya Yoshida, Hiroyuki Okazaki, Keisuke Iwai, Kengo Noami, Takayuki Muro, Mario Okawa, Kyoko Ishizaka, Shik Shin, Zheng Li, Jianlin Luo, Guo-qing Zheng, Tamio Oguchi, Masaaki Hirai, Yuji Muraoka, Takayoshi Yokoya

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   78 ( 3 ) 34705  2009.03  [Refereed]

     View Summary

    We report the results of first photoemission spectroscopy on a newly discovered noncentrosymmetric superconductor Mg10Ir19B16. We measured the valence band structure of Mg10Ir19B16 using soft X-ray photoemission technique and found that the first principal calculation explains our observation well. In the bulk-sensitive laser-excited photoemission study, we observed that the intensity at the Fermi level decreases as we lower the sample temperature, indicative of the opening of superconducting energy gap. Using Dynes' function, we performed fitting analysis on the spectra of superconducting state.

    DOI

  • Electronic Structure of Superconducting FeSe Studied by High-Resolution Photoemission Spectroscopy

    Rikiya Yoshida, Takanori Wakita, Hiroyuki Okazaki, Yoshikazu Mizuguchi, Shunsuke Tsuda, Yoshihiko Takano, Hiroyuki Takeya, Kazuto Hirata, Takayuki Muro, Mario Okawa, Kyoko Ishizaka, Shik Shin, Hisatomo Harima, Masaaki Hirai, Yuji Muraoka, Takayoshi Yokoya

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   78 ( 3 ) 34708  2009.03  [Refereed]

     View Summary

    We have pet-formed soft x-ray and Ultralligh-resolution laser-excited photoemission measurements on tetragonal FeSe, which was recently identified as a superconductor. Energy dependent study of valence band is compared to band Structure Calculations and yields a reasonable assignment of partial densities of states. However, the sharp peak near the Fermi level slightly deviates from the calculated energy position, giving rise to the necessity of self energy correction. We have also performed ultrahigh-resolution laser photoemission experiment on FeSe and observed the suppression of intensity around the Fermi level upon cooling.

    DOI

  • Temperature-dependent pseudogap in the oxypnictides LaFeAsO1-xFx and LaFePO1-xFx seen via angle-integrated photoemission

    Y. Ishida, T. Shimojima, K. Ishizaka, T. Kiss, M. Okawa, T. Togashi, S. Watanabe, X. -Y. Wang, C. -T. Chen, Y. Kamihara, M. Hirano, H. Hosono, S. Shin

    PHYSICAL REVIEW B   79 ( 6 ) 060503  2009.02  [Refereed]

     View Summary

    We have performed a temperature-dependent angle-integrated laser photoemission study of iron oxypnictide superconductors LaFeAsO:F and LaFePO:F exhibiting critical-transition temperatures (T-c&apos;s) of 26 and 5 K, respectively. We find that high-T-c LaFeAsO:F exhibits a temperature-dependent pseudogaplike feature extending over similar to 0.1 eV about the Fermi level at 250 K, whereas such a feature is absent in low-T-c LaFePO:F. We also find similar to 20-meV pseudogaplike features and signatures of superconducting gaps in both LaFeAsO:F and LaFePO:F. We discuss the possible origins of the unusual pseudogaplike features through comparison with the high-T-c cuprates.

    DOI

  • Momentum dependence of the energy gap in the superconducting state of optimally doped Bi-2(Sr,R)(2)CuOy (R=La and Eu)

    Y. Okada, T. Takeuchi, M. Ohkawa, A. Shimoyamada, K. Ishizaka, T. Kiss, S. Shin, H. Ikuta

    25TH INTERNATIONAL CONFERENCE ON LOW TEMPERATURE PHYSICS (LT25), PART 5   150   52197  2009  [Refereed]

     View Summary

    The energy gap of optimally doped Bi-2(Sr,R)(2)CuOy (R=La and Eu) was probed by angle resolved photoemission spectroscopy (ARPES) using a vacuum ultraviolet laser (photon energy 6.994 eV) or He I a resonance line (21.218 eV) as photon source. The results show that the gap around the node at sufficiently low temperatures can be well described by a monotonic d-wave gap function for both samples and the gap of the R=La sample is larger reflecting the higher T c. However, an abrupt deviation from the d-wave gap function and an opposite R dependence for the gap size were observed around the antinode, which represent a clear disentanglement between the antinodal pseudogap and the nodal superconducting gap.

    DOI

  • Doping-dependence of nodal quasiparticle properties in high-T(c) cuprates studied by laser-excited angle-resolved photoemission spectroscopy

    K. Ishizaka, T. Kiss, S. Izumi, M. Okawa, T. Shimojima, A. Chainani, T. Togashi, S. Watanabe, C. -T. Chen, X. Y. Wang, T. Mochiku, T. Nakane, K. Hirata, S. Shin

    PHYSICAL REVIEW B   77 ( 6 ) 064522  2008.02  [Refereed]

     View Summary

    We investigate the doping dependent low-energy, low temperature (T=5 K) properties of nodal quasiparticles in the d-wave superconductor Bi(2.1)Sr(1.9)CaCu(2)O(8+delta) (Bi2212). By utilizing ultrahigh resolution laser-excited angle-resolved photoemission spectroscopy, we obtain precise band dispersions near E(F), mean free paths, and scattering rates (Gamma) of quasiparticles. For optimally and overdoped samples, we obtain very sharp quasiparticle peaks of 8 and 6 meV full width at half maximum, respectively. The value of Gamma for optimally doped sample is in good accordance with terahertz conductivity. For all doping levels, we find the energy dependence of Gamma similar to vertical bar omega vertical bar, while Gamma(omega=0) shows a monotonic increase from overdoping to underdoping. The doping-dependence suggests the role of electronic inhomogeneity on the nodal quasiparticle scattering at low temperature (5 K less than or similar to 0.07T(c)) pronounced in the underdoped region. The quasiparticle peak spectra match well with a single Lorentzian function, thus indicating that the nodal carriers can be described as well-defined quasiparticles, even in the underdoped region.

    DOI CiNii

  • Unusual pseudogap features observed in iron oxypnictide superconductors

    Yukiaki Ishida, Takahiro Shimojima, Kyoko Ishizaka, Takayuki Kiss, Mario Okawa, Tadashi Togashi, Shuntaro Watanabe, Xiaoyang Wang, Chuangtian Chen, Yoichi Kamihara, Masahiro Hirano, Hideo Hosono, Shik Shin

    Journal of the Physical Society of Japan   77 ( C ) 61 - 64  2008  [Refereed]

     View Summary

    We present angle-integrated photoemission spectroscopy (PES) study of LaOFeAs:F (Tc = 26 K) and LaOFeP:F (Tc = 5 K) using He I line (h? = 21.2 eV) and laser (h? = 6.994 eV) as excitation light sources. We find quantitatively consistent results between the He I and the laser PES measurements: LaFeAsO:F exhibits a temperature-dependent pseudogap as large as ∼0.1 eV at 300 K, whereas LaFePO:F exhibits a ∼20-meV pseudogap. We discuss possible origin of the T -dependent pseudogap specifically observed in LaFeAsO:F through comparison with other materials that exhibit unusual T -dependent pseudogaps. ©2008 The Physical Society of Japan.

    DOI

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Misc

  • Emergent photovoltage on SmB6 surface upon bulk-gap evolution revealed by pump-and-probe photoemission spectroscopy (vol 5, 8160, 2015)

    Y. Ishida, T. Otsu, T. Shimada, M. Okawa, Y. Kobayashi, F. Iga, T. Takabatake, S. Shin

    SCIENTIFIC REPORTS   5  2015.05

    Other  

    DOI

  • 7pBG-2 Electronic structure of LaCo_<1-x>Rh_xO_3 : Comparison of HX-PES and band calculation

    Okada R., Taji T., Okawa M., Wadati H., Yoshida T., Kobayashi Y., Terakado Y., Asai K., Kozina Xeniya, Ikenaga E., Sakai E., Kumigashira H., Hamada N., Saitoh T.

    Meeting abstracts of the Physical Society of Japan   69 ( 2 ) 338 - 338  2014.08

    CiNii

  • 8aBG-4 Electronic structure of delaffosite oxides CuMO_2 (M=Cr,Al,Fe)

    Kato R., Okawa M., Ono K., Okuda T., Ikenaga E., Wadati H., Yoshida T., Saitoh T.

    Meeting abstracts of the Physical Society of Japan   69 ( 2 ) 349 - 349  2014.08

    CiNii

  • 29pPSA-6 Electronic structure of a triangular-based lattice compound Ba_2Ti_<13>O_<22> by photoemission spectroscopy

    Sekine S., Kojima H., Okawa M., Ono K., Takayama K., Katsufuji T., Saitoh T.

    Meeting abstracts of the Physical Society of Japan   69 ( 1 ) 761 - 761  2014.03

    CiNii

  • 28pAS-4 Electronic structure of CuMO_2(M=Al,Fe) studied by photoemission spectroscopy

    Kato R., Okawa M., Wadati H., Yoshida T., Kozina Xeniya, Ikenaga E., Ono K., Okuda T., Saitoh T.

    Meeting abstracts of the Physical Society of Japan   69 ( 1 ) 750 - 750  2014.03

    CiNii

  • 28pAS-3 Photoemission Study of LaCo_<1-x>Rh_xO_3

    Okada R., Taji T., Okawa M., Wadati H., Yoshida T., Kobayashi Y., Terakado Y., Asai K., Kozina Xeniya, Ikenaga E., Sakai E., Kumigashira H., Nakatake M., Namatame H., Taniguchi M., Saitoh T.

    Meeting abstracts of the Physical Society of Japan   69 ( 1 ) 749 - 749  2014.03

    CiNii

  • Improving the Smart Radiation Device with Perovskite Mn Oxides(2)

    Tanaka K., Tachikawa S., Kuwahara H., Okawa M., Saitoh T.

    Meeting abstracts of the Physical Society of Japan   68 ( 2 ) 539 - 539  2013.08

    CiNii

  • 29aEJ-5 The electronic structure of CuCr_<1-x>Mg_xO_2 studied using photoemission spectroscopy and soft X-ray absorption spectroscopy

    Konishi K., Yokobori T., Okawa M., Takei R., Katayama K., Oozono S., Shinmura T., Okuda T., Wadati H., Sakai E., Ono K., Kumigashira H., Oshima M., Sugiyama T., Ikenaga E., Hamada N., Saitoh T.

    Meeting abstracts of the Physical Society of Japan   68 ( 1 ) 854 - 854  2013.03

    CiNii

  • 価数揺動系α-Yb(Al,Fe)B4におけるYb価数のFeドープ・温度依存性

    大川万里生, 笠原聡, 田路智也, 山村周玄, 和達大樹, 吉田鉄平, 杉山武晴, 池永英司, 田口宗孝, 辛埴, 辛埴, 久我健太郎, 中辻知, 齋藤智彦

    日本物理学会講演概要集   68 ( 2 )  2013

    J-GLOBAL

  • 20pFG-16 Improving the Smart Radiation Device with Perovskite Mn Oxides

    Tanaka K., Tachikawa S., Kuwahara H., Okawa M., Saitoh T.

    Meeting abstracts of the Physical Society of Japan   67 ( 2 ) 546 - 546  2012.08

    CiNii

  • 25pCK-1 Surface states of Cu_xBi_2Se_3 and SrTiO_3 observed by circular-dichroism ARPES

    Ishida Y., Kanto H., Kikkawa A., Taguchi Y., Ito Y., Ota Y., Okazaki K., Malaeb Walid, Mulazzi Mattia, Okawa M., Watanabe S., Chen Chuangtian, Kim M., Bell Christopher, Kozuka Y., Hwang Halord Y., Tokura Y., Shin S.

    Meeting abstracts of the Physical Society of Japan   67 ( 1 ) 948 - 948  2012.03

    CiNii

  • 27aAC-4 X-Ray Absorption Spectroscopy of Double-Perovskite Cobaltates

    Okawa M., Hasegawa A., Nishimura J., Wadati H., Takubo K., Mizokawa T., Regier Tom Z., Kobayashi Y., Terakado Y., Arai N., Asai Y., Saitoh T.

    Meeting abstracts of the Physical Society of Japan   67 ( 1 ) 816 - 816  2012.03

    CiNii

  • 26pAD-4 The electronic structure of CuCr_<1-x>Mg_xO_2 and Mg doping dependence

    Yokobori T., Konishi K., Takei R., Katayama K., Okawa M., Oozono S., Shinmura T., Okuda T., Wadati H., Sugiyama T., Ikenaga E., Ono K., Hamada N., Saitoh T.

    Meeting abstracts of the Physical Society of Japan   67 ( 1 ) 810 - 810  2012.03

    CiNii

  • 26pAD-5 Electronic structuter in Sr_3Fe_<2-x>Co_xO_<7-δ>

    Naito R, Ikenaga H, Kumigasira H, Sakai E, Saitoh T, Nakano Y, Okawa M, Wadachi D, Nakamura R, Tozawa J, Akagi N, Kuwahara H, Sugiyama T

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

    CiNii

  • Two-Fermi-Surface Superconducting State and a Nodal d-Wave Energy Gap of the Electron-Doped Sm1.85Ce0.15CuO4-delta Cuprate Superconductor (vol 106, 197002, 2011)

    A. F. Santander-Syro, M. Ikeda, T. Yoshida, A. Fujimori, K. Ishizaka, M. Okawa, S. Shin, B. Liang, A. Zimmers, R. L. Greene, N. Bontemps

    PHYSICAL REVIEW LETTERS   107 ( 7 )  2011.08

    Other  

    DOI

  • 高分解能レーザー励起角度分解光電子分光による不足ドープBi2(Sr1-xLaχ)2CuO6+δの超伝導ギャップのキャリア濃度依存性

    小川古都, 竹内恒博, 竹内恒博, 大川万里生, 辛埴

    日本放射光学会年会・放射光科学合同シンポジウム予稿集   24th  2011

    J-GLOBAL

  • 不足ドープBi2(Sr1-xLax)2CuO6+δの超伝導ギャップのキャリア濃度依存性

    小川古都, HONG J., 竹内垣博, 竹内垣博, 竹内垣博, 生田博志, 生田博志, MALACB Walid, 大川万里生, SHIN S.

    日本物理学会講演概要集   66 ( 1 )  2011

    J-GLOBAL

  • レーザー光電子分光によるデツインされたBaFe2As2の電子状態の研究

    園部竜也, 下志万貴博, 坂野昌人, 大川万里生, MALAEB W., MALAEB W., 富樫格, 渡部俊太郎, SHIN S., SHIN S., SHIN S., 中島正道, 中島正道, 中島正道, 石田茂之, 石田茂之, 石田茂之, 内田慎一, 富岡泰秀, 富岡泰秀, 木方邦宏, 木方邦宏, LEE C., LEE C., 伊豫彰, 伊豫彰, 永崎洋, 永崎洋, 伊藤利充, 伊藤利充, 石坂香子

    日本物理学会講演概要集   66 ( 1 )  2011

    J-GLOBAL

  • レーザー光電子分光によるデツインされたBaFe2As2の電子状態の研究 2

    園部竜也, 下志万貴博, 坂野昌人, 大川万里生, MALAEB W., MALAEB W., 富樫格, 渡部俊太郎, 辛埴, 辛埴, 辛埴, 中島正道, 中島正道, 中島正道, 石田茂之, 石田茂之, 石田茂之, 内田慎一, 富岡泰秀, 富岡泰秀, 木方邦宏, 木方邦宏, LEE C., LEE C., 伊豫彰, 伊豫彰, 永崎洋, 永崎洋, 伊藤利充, 伊藤利充, 石坂香子

    日本物理学会講演概要集   66 ( 2 )  2011

    J-GLOBAL

  • 23pGB-6 Photoemission spectroscopy of double perovskite cobalt oxides

    Hasegawa A, Nakatake M, Jiang J, Shimada K, Namatame H, Taniguchi M, Ueda S, Yamashita Y, Yoshikawa H, Kobayashi K, Nishimura J, Saitoh T, Okawa M, Kobayashi Y, Terakado Y, Arai N, Asai K, Hamada N

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

    CiNii

  • 22aGC-13 Quantum Critical Phenomena Induced by Fe doping in the Valence Fluctuating Heavy Fermion System α-YbAlB_4

    Kuga K, O'Farrell E. C. T, Matsumoto Y, Nakatsuji S, Okawa M, Takata Y, Matsunami M, Eguchi R, Taguchi M, Chainani Ashish, Shin S, Nishino Y, Tamasaku K, Yabashi M, Ishikawa T, Kiuchi Y

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

    CiNii J-GLOBAL

  • 26aEC-4 Magnetism and Valence Change Induced by Fe doping in the Valence Fluctuating Heavy Fermion System α-YbAlB_4

    Kuga K, Matsumoto Y, Nakatsuji S, Okawa M, Takata Y, Matsunami M, Eguchi R, Taguchi M, Chainani Ashish, Shin S, Nishino Y, Tamasaku K, Yabashi M, Ishikawa T, Kiuchi Y

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

    CiNii

  • 20pPSB-12 Substitution effect on electronic state of FeSe

    Tsuda S, Mizuguchi Y, Yamaguchi T, Takano Y, Okawa M, Ishida Y, Ishizaka K, Shin S, Watanabe S, Chen C. -T

    Meeting abstracts of the Physical Society of Japan   65 ( 1 )  2010.03

    CiNii

  • FeSeの電子状態における置換効果 II

    津田俊輔, 津田俊輔, 水口佳一, 水口佳一, 水口佳一, 山口尚秀, 高野義彦, 高野義彦, 高野義彦, 大川万里生, 石田行章, 石坂香子, 辛埴, 辛埴, 渡部俊太郎, CHEN C.‐T

    日本物理学会講演概要集   65 ( 1 ) 579  2010.03

    J-GLOBAL

  • 20pGH-5 Laser angle-resolved photoemission study on BaFe_2(As_<0.67>P_<0.33>)_2 : Observation of Fermi surface and Superconducting gap II

    Sakaguchi F, Shimojima T, Ishizaka K, Ishida Y, Okawa M, Kiss T, Togashi T, Wang X. -Y, Chen C. T, Watanabe S, Kasahara S, Shibauchi T, Matsuda Y, Takeya H, Hirata K, Terashima T, Shin S

    Meeting abstracts of the Physical Society of Japan   65 ( 1 )  2010.03

    CiNii

  • 不足ドープBi2(Sr1-xLax)2CuO6+δの超伝導ギャップのキャリア濃度依存性

    小川古都, 浜谷陽一郎, 生田博志, 竹内恒博, 竹内恒博, 大川万里生, 石坂香子, 辛埴

    日本物理学会講演概要集   65 ( 1 )  2010

    J-GLOBAL

  • 23aGH-3 Laser angle-resolved photoemission study on FeSe1-x(Tex)

    Ito Y., Wang X.-Y., Chen C. T., Shin S., Shimojima T., Ishizaka K., Okawa M., Kiss T., Watanabe S., Niitaka S., Hanaguri T., Takagi H.

    Meeting Abstracts of the Physical Society of Japan   65 ( 0 ) 674 - 674  2010

    DOI CiNii J-GLOBAL

  • 25pRL-11 Substitution effect on electronic state of FeSe

    Tsuda S, Mizuguchi Y, Yamaguchi T, Takano Y, Okawa M, Ishida Y, Ishizaka K, Shin S, Watanabe S, Chen C. -T

    Meeting abstracts of the Physical Society of Japan   64 ( 2 )  2009.08

    CiNii

  • FeSeの電子状態における置換効果

    津田俊輔, 津田俊輔, 水口佳一, 水口佳一, 水口佳一, 山口尚秀, 高野義彦, 高野義彦, 高野義彦, 大川万里生, 石田行章, 石坂香子, SHIN S, SHIN S, 渡部俊太郎, CHEN C.‐T

    日本物理学会講演概要集   64 ( 2 ) 458  2009.08

    J-GLOBAL

  • 25pRL-5 Laser angle-resolved photoemission study on BaFe_2(As_<0.67>P_<0.33)_2 : Observation of Fermi surface and Superconducting gap

    Sakaguchi F, Shimojima T, Ishizaka K, Ishida Y, Okawa M, Kiss T, Togashi T, Wang X. -Y, Chen C. T, Watanabe S, Kasahara S, Shibauchi T, Matsuda Y, Takeya H, Hirata K, Terashima T, Shin S

    Meeting abstracts of the Physical Society of Japan   64 ( 2 )  2009.08

    CiNii

  • 重い電子系Yb(Al,Fe)B4におけるYb価数のFe置換依存性

    大川万里生, 松波雅治, 石坂香子, 江口律子, 田口宗孝, CHAINANI Ashish, 高田恭孝, 矢橋牧名, 玉作賢治, 西野吉則, 石川哲也, 久我健太郎, 堀江直樹, 中辻知, SHIN S

    日本物理学会講演概要集   64 ( 2 ) 563  2009.08

    J-GLOBAL

  • 30pTC-7 Electronic structure of FeSe superconductor

    Yoshida R, Wakita T, Okazaki H, Mizuguchi Y, Tsuda S, Takano Y, Takeya H, Hirata K, Muro T, Okawa M, Ishizaka K, Shin S, Harima H, Hirai M, Muraoka Y, Yokoya T

    Meeting abstracts of the Physical Society of Japan   64 ( 1 )  2009.03

    DOI CiNii

  • FeSe超伝導体の電子状態

    吉田力矢, 脇田高徳, 脇田高徳, 岡崎宏之, 水口佳一, 水口佳一, 水口佳一, 津田俊輔, 津田俊輔, 高野義彦, 高野義彦, 高野義彦, 竹屋浩幸, 平田和人, 室隆桂之, 大川万里生, 石坂香子, SHIN S, 播磨尚朝, 播磨尚朝, 平井正明, 平井正明, 平井正明, 村岡祐治, 村岡祐治, 村岡祐治, 横谷尚睦, 横谷尚睦, 横谷尚睦, 津田俊輔

    日本物理学会講演概要集   64 ( 1 ) 662  2009.03

    J-GLOBAL

  • FeSe関連物質における高分解能光電子分光

    津田俊輔, 津田俊輔, 水口佳一, 水口佳一, 水口佳一, 冨岡史明, 山口尚秀, 高野義彦, 高野義彦, 高野義彦, 大川万里生, 石田行章, 石坂香子, SHIN S, SHIN S, 渡部俊太郎, CHEN C.‐T

    日本物理学会講演概要集   64 ( 1 ) 662  2009.03

    J-GLOBAL

  • 30aTD-5 Photoemission spectroscopy of heavy-fermion system YbAlB_4 : Electronic structure and valence estimation

    Okawa M, Matsunami M, Ishizaka K, Eguchi R, Taguchi M, Chainani Ashish, Takata Y, Yabashi M, Tamasaku K, Nishino Y, Ishikawa T, Kuga K, Horie N, Nakatsuji S, Shin S

    Meeting Abstracts of the Physical Society of Japan   64 ( 0 )  2009

    CiNii

  • Electronic Structure of Superconducting FeSe Studied by High-Resolution Photoemission Spectroscopy

    Rikiya Yoshida, Takanori Wakita, Hiroyuki Okazaki, Yoshikazu Mizuguchi, Shunsuke Tsuda, Yoshihiko Takano, Hiroyuki Takeya, Kazuto Hirata, Takayuki Muro, Mario Okawa, Kyoko Ishizaka, Shik Shin, Hisatomo Harima, Masaaki Hirai, Yuji Muraoka, Takayoshi Yokoya

    J. Phys. Soc. Jpn. 78, 034708 (2009)   64 ( 1 )  2008.11

    Internal/External technical report, pre-print, etc.  

     View Summary

    We have performed soft x-ray and ultrahigh-resolution laser-excited<br />
    photoemission measurements on tetragonal FeSe, which was recently identified as<br />
    a superconductor. Energy dependent study of valence band is compared to band<br />
    structure calculations and yields a reasonable assignment of partial densities<br />
    of states. However, the sharp peak near the Fermi level slightly deviates from<br />
    the calculated energy position, giving rise to the necessity of self-energy<br />
    correction. We have also performed ultrahigh-resolution laser photoemission<br />
    experiment on FeSe and observed the suppression of intensity around the Fermi<br />
    level upon cooling.

    DOI CiNii

  • Bi2(Sr,R)2CuOyにおけるノード近傍の電子状態のR依存性

    岡田佳憲, 竹内恒博, 石坂香子, 大川万里生, 下山田篤史, 辛埴, 生田博志

    日本物理学会講演概要集   63 ( 1 )  2008

    J-GLOBAL

  • Bi2(Sr,R)2CuOyにおけるノード近傍の電子状態のR依存性 II

    川口昂彦, 岡田佳憲, 竹内恒博, 石坂香子, 大川万里生, 辛植, 生田博志

    日本物理学会講演概要集   63 ( 2 )  2008

    J-GLOBAL

▼display all

Research Projects

Presentations

  • Electronic structure of Pr1-xYxCoO3 probed by photoemission spectroscopy

    D. Kanai, R. Takayanagi, M. Okawa, Y. Kobayashi, M. Kobayashi, M. Minohara, K. Horiba, H. Kumigashira, A. Yasui, E. Ikenaga, T. Saitoh

    International Workshop on Trends in Advanced Spectroscopy in Materials Science (TASPEC)  (Hiroshima University, Higashi-Hiroshima, Japan) 

    Presentation date: 2018.10

  • 時間分解角度分解光電子分光によるLa1.2Sr1.8Mn2O7の電子構造の研究

    大久保晶平, 宮林麟太郎, 渡邉真莉, 大川万里生, 鈴木剛, 藤澤正美, 金井輝人, 石井順久, 板谷治郎, 野田正亮, 桑原英樹, 岡崎浩三, 辛埴, 齋藤智彦

    日本物理学会2018年秋季大会  (同志社大学京田辺キャンパス) 

    Presentation date: 2018.09

  • X線光電子分光によるBa3-xSrxNb5O15の電子状態

    安田辰徳, 大川万里生, 溝川貴司, 金銅勇輝, 梶田倫正, 勝藤拓郎, 齋藤智彦, 雀部矩正, 木康多, 保井晃, 中谷俊介, 宮林麟太郎

    日本物理学会2018年秋季大会  (同志社大学京田辺キャンパス) 

    Presentation date: 2018.09

  • 宇宙機ラジエータに応用するペロブスカイト型Mn酸化物の硬X線光電子分光法による価電子帯電子構造研究

    中谷俊介, 飯尾大貴, 大川万里生, 太刀川純孝, 桑原英樹, 保井晃, 高木康多, 池永英司, 齋藤智彦

    日本物理学会2018年秋季大会  (同志社大学京田辺キャンパス) 

    Presentation date: 2018.09

  • 硬X線光電子分光法による La0.775Sr0.225-xCaxMn1-yGayO3の電子構造

    飯尾大貴, 大川万里生, 保井晃, 池永英司, 高木康多, 桑原英樹, 太刀川純孝, 齋藤智彦

    日本物理学会2018年秋季大会  (同志社大学京田辺キャンパス) 

    Presentation date: 2018.09

  • 共鳴光電子分光法によるPr1-xYxCoO3の電子構造の研究II

    金井大輔, 高柳亮平, 中村拓海, 大川万里生, 小林義彦, 小林正起, 簑原誠人, 堀場弘司, 組頭広志, 小野寛太, Eike F. Schwier, 島田賢也, 齋藤智彦

    日本物理学会2018年秋季大会  (同志社大学京田辺キャンパス) 

    Presentation date: 2018.09

  • ARPESによる層状Mn酸化物La2-2xSr1+2xMn2O7(x?0.5)の電子構造の研究

    宮林麟太郎, 高橋裕也, 大久保晶平, 大川万里生, 桑原英樹, 野田正亮, 齋藤智彦

    日本物理学会2018年秋季大会  (同志社大学京田辺キャンパス) 

    Presentation date: 2018.09

  • La1-xSrxMnO3 価電子帯光電子分光スペクトルのhν依存性

    下山諒太, 大江日南子, 大川万里生, 菱田智子, 大林和重, 保井晃, 池永英司, 齋藤智彦

    日本物理学会 第73回年次大会  (東京理科大学野田キャンパス) 

    Presentation date: 2018.03

  • La1-xSrxMnO3におけるMn 2p硬X線光電子分光スペクトルのホールドープ量・温度依存性

    大江日南子, 下山諒太, 大川万里生, 野田正亮, 菱田智子, 大林和重, 保井晃, 池永英司, 桑原英樹, 齋藤智彦

    日本物理学会 第73回年次大会  (東京理科大学野田キャンパス) 

    Presentation date: 2018.03

  • 角度分解光電子分光によるLa2-2xSr1+2xMn2O7(x〜0.5)の電子構造と電子相の研究

    大久保晶平, 高橋裕也, 宮林麟太郎, 大川万里生, 桑原英樹, 野田正亮, 齋藤智彦

    日本物理学会 第73回年次大会  (東京理科大学野田キャンパス) 

    Presentation date: 2018.03

  • Temperature dependence of valence-band and Co 2p hard x-ray photoemission spectra in LaCoO3

    高柳亮平, 金井大輔, 大川万里生, 小林義彦, 保井晃, 池永英司, 齋藤智彦

    日本物理学会 第73回年次大会  (東京理科大学野田キャンパス) 

    Presentation date: 2018.03

  • 共鳴光電子分光法によるPr1-xYxCoO3

    金井大輔, 高柳亮平, 大川万里生, 小林義彦, 小野寛太, 堀場弘司, Eike F. Schwier, 島田賢也, 齋藤智彦

    日本物理学会 第73回年次大会  (東京理科大学野田キャンパス) 

    Presentation date: 2018.03

  • スピネル型酸化物AlV2O4の硬X線光電子分光

    大川万里生, 下山諒太, 高柳亮平, 飯尾大樹, 大江日南子, 金井大輔, 保井晃, 池永英司, 勝藤拓郎, 溝川貴司, 齋藤智彦

    日本物理学会2017年秋季大会  (岩手大学 上田キャンパス) 

    Presentation date: 2017.09

  • Pr1-xYxCoO3における光電子分光スペクトルのドープ量依存性

    高柳亮平, 金井大輔, 大川万里生, 小林義彦A, 保井晃, 池永英司, 小林正起, 蓑原誠人, 堀場弘司, 組頭広志, 小野寛太, 齋藤智彦

    日本物理学会2017年秋季大会  (岩手大学 上田キャンパス) 

    Presentation date: 2017.09

  • 銅系クレドネライト型酸化物Cu1+xMn1-xO2(x = 0, 0.10, 0.15)の電子構造

    高橋謙太, 大川万里生, 保井晃, 池永英司, 奥田哲治, 浜田典昭, 小野寛太, 齋藤智彦

    日本物理学会2017年秋季大会  (岩手大学 上田キャンパス) 

    Presentation date: 2017.09

  • Instable electronic/magnetic ground state in La2-2xSr1+2xMn2O7 (x〜0.5) probed by ARPES

    Yuya Takahashi, Mario Okawa, Hideki Kuwahara, Kanta Ono, Tomohiko Saitoh

    International Workshop on Strong Correlations and Angle-Resolved Photoemission Spectroscopy (CORPES17)  (Hiroshima, Japan) 

    Presentation date: 2017.07

  • Co 2p hard x-ray photoemission spectra of perovskite Co oxides as a manifestation of complex spin state

    Ryohei Takayanagi, Shohei Takei, Mario Okawa, Yoshihiko Kobayashi, Akira Yasui, Eiji Ikenaga, Tomohiko Saitoh

    International Workshop on Strong Correlations and Angle-Resolved Photoemission Spectroscopy (CORPES17)  (Hiroshima, Japan) 

    Presentation date: 2017.07

  • Non-Fermi liquid behavior in the Vicinity of Metal to Insulator Transition in Nd1-xSrxVO3 probed by Photoemission Spectroscopy

    Daiki Ootsuki, S. Yamamoto, D. Shimonaka, D. Shibata, K. Kodera, M. Okawa, T. Saitoh, M. Horio, A. Fujimori, H. Kumigashira, K. Ono, E. Ikenaga, S. Miyasaka, S. Tajima, Teppei Yoshida

    International Workshop on Strong Correlations and Angle-Resolved Photoemission Spectroscopy (CORPES17)  (Hiroshima, Japan) 

    Presentation date: 2017.07

  • Cu+-M3+ charge transfer effect in Cu-based delafossite oxides revealed by photoemission spectroscopy

    Mario Okawa, Ryo Kato, Akira Yasui, Eiji Ikenaga, Kanta Ono, Tetsuji Okuda, Tomohiko Saitoh

    International Workshop on Strong Correlations and Angle-Resolved Photoemission Spectroscopy (CORPES17)  (Hiroshima, Japan) 

    Presentation date: 2017.07

  • Hard x-ray photoemission spectra of the Mn 2p core level in colossal magnetoresistive La1-xSrxMnO3

    Ryota Shimoyama, Mario Okawa, Tomoko Hishida, Kazushige Ohbayashi, Akira Yasui, Eiji Ikenaga, Tomohiko Saitoh

    International Workshop on Strong Correlations and Angle-Resolved Photoemission Spectroscopy (CORPES17)  (Hiroshima, Japan) 

    Presentation date: 2017.07

  • Polarization-emission angle dependent hard x-ray photoemission study on Cu-based delafossite oxides

    Kenta Takahashi, Mario Okawa, Akira Yasui, Eiji Ikenaga, Sumito Ogata, Masato Ota, Tetsuji Okuda, Noriaki Hamada, Tomohiko Saitoh

    International Workshop on Strong Correlations and Angle-Resolved Photoemission Spectroscopy (CORPES17)  (Hiroshima, Japan) 

    Presentation date: 2017.07

  • 光電子分光によるNd1-xSrxVO3の金属絶縁体転移近傍における擬ギャップ構造の観測

    大槻太毅, 山本紳太郎, 下中大也, 柴田大輔, 小寺健二朗, 大川万里生, 齋藤智彦, 堀尾眞史, 藤森敦, 組頭広志, 小野寛太, 池永英司, 宮坂茂樹, 田島節子, 吉田鉄平

    日本物理学会第72回年次大会  (大阪大学豊中キャンパス) 

    Presentation date: 2017.03

  • 硬X線光電子分光によるLa1-xSrxMnO3の電子状態

    下山諒太, 大川万里生, 菱田智子, 大林和重, 保井晃, 池永英司, 齋藤智彦

    日本物理学会第72回年次大会  (大阪大学豊中キャンパス) 

    Presentation date: 2017.03

  • 高分解能角度分解光電子分光による高機能物質における新たな量子物質相の探索

    高橋隆, 佐藤宇史, 相馬清吾, 中山耕輔, 菅原克明, 藤森淳, 堀尾眞史, 吉田鉄平, 齋藤智彦, 大川万里生, 石坂香子, 下志万貴博, 組頭広志, 小野寛太

    2016年度量子ビームサイエンスフェスタ・第34回PFシンポジウム  (つくば国際会議場(エポカルつくば)) 

    Presentation date: 2017.03

  • デラフォサイト型酸化物CuMO2(M:3価金属)の硬X線光電子分光スペクトルの直線変更依存性

    ????A?, A?, W?A?r?i?, A?, c?N。?A?, l?A??c?^?P?A?l?c?T?A?, q?F

    第30回日本放射光学会年会・放射光科学合同シンポジウム  (神戸芸術センター) 

    Presentation date: 2017.01

  • Co 2p 内殻硬X線光電子分光によるペロブスカイト型Co酸化物のスピン状態の研究

    高柳亮平, 武井翔平, 大川万里生, 小林義彦, 保井晃, 池永英司, 齋藤智彦

    第30回日本放射光学会年会・放射光科学合同シンポジウム  (神戸芸術センター) 

    Presentation date: 2017.01

  • 巨大磁気抵抗物質La1-xSrxMnO3における硬X線光電子分光スペクトルのドープ量依存性

    下山諒太, 大川万里生, 菱田智子, 大林和重, 保井晃, 池永英司, 齋藤智彦

    第30回日本放射光学会年会・放射光科学合同シンポジウム  (神戸芸術センター) 

    Presentation date: 2017.01

  • VO2を用いた放射率可変ラジエータの検討―単結晶VO2の熱放射特製の測定―

    山本早伽, 畑真尋, 田中洸輔, 太刀川純孝, 大川万里生, 齋藤智彦

    第37回日本熱物性シンポジウム  (岡山国際交流センター) 

    Presentation date: 2016.11

  • 銅系デラフォサイト型酸化物CuMO2(M:3価金属)の直線偏光依存硬X線光電子分光

    高橋謙太, 大川万里生, 保井晃, 池永英司, 奥田哲治, 尾方済人, 大田真輝, 浜田典昭, 齋藤智彦

    日本物理学会2016年秋季大会  (金沢大学角間キャンパス) 

    Presentation date: 2016.09

  • ペロブスカイト型Co酸化物のスピン状態と硬X線光電子分光スペクトルの関係

    高柳亮平, 武井翔平, 大川万里生, 小林義彦, 保井晃, 池永英司, 齋藤智彦

    日本物理学会2016年秋季大会  (金沢大学角間キャンパス) 

    Presentation date: 2016.09

  • 角度分解光電子分光による層状Mn酸化物の電子構造と電子相の研究

    岡村直哉, 大川万里生, 小野寛太, 桑原英樹, 齋藤智彦

    日本物理学会2016年秋季大会  (金沢大学角間キャンパス) 

    Presentation date: 2016.09

  • Mn酸化物を用いた宇宙機用放射率可変素子(SRD)の研究―還元アニールによる電気抵抗率・帯磁率・放射率の変化―

    畑真尋, 太刀川純孝, 小田涼佑, 野田正亮, 桑原英樹, 大川万里生, 齋藤智彦

    第77回応用物理学会秋季学術講演会  (朱鷺(とき)メッセ(新潟市)) 

    Presentation date: 2016.09

  • 小惑星探査機用指向性ラジエータの研究―熱放射特製の測定―

    山本早伽, 太刀川純孝, 大川万里生, 齋藤智彦

    第60回宇宙科学技術連合講演会  (函館アリーナ) 

    Presentation date: 2016.09

  • 単相流体を用いた小型宇宙機用熱マネジメントシステムに関する研究

    江口駿作, 太刀川純孝, 齋藤智彦, 大川万里生, 小川博之

    第60回宇宙科学技術連合講演会  (函館アリーナ) 

    Presentation date: 2016.09

  • Study on electrical conductivity of (La,Sr)MnO3 by x-ray photoemission spectroscopy

    T. Hishida, H. Kozuka, M. Kobata, E. Ikenaga, T. Sugiyama, K. Ohbayashi, K. Kobayashi, M. Okawa, T. Saitoh

    The 13th International Conference on Ceramic Processing Science  (Todai-ji Culture Center & Nara Kasugano International Forum, Nara) 

    Presentation date: 2016.05

  • 三角格子を持つV酸化物の電子状態と軌道電荷整列

    吉野翼, 野田智博, 溝川貴司, 大川万里生, 齋藤智彦, 小林正起, 堀場弘司, 小野寛太, 組頭広志, 梶田倫正, 勝藤拓郎

    日本物理学会第71回年次大会  (東北学院大学泉キャンパス) 

    Presentation date: 2016.03

  • 角度分解光電子分光法による層状Mn酸化物の電子構造

    今井駿, 高山勇武, 小川晃平, 桑原英樹, 小野寛太, 大川万里生, 齋藤智彦

    第29回日本放射光学会年会・放射光科学合同シンポジウム  (柏の葉カンファレンスセンター) 

    Presentation date: 2016.01

  • Cu1+xMn1-xO2(x=0,0.05)の電子構造

    加藤諒, 大川万里生, 和達大樹, 吉田鉄平, 小野寛太, 池永英司, 奥田哲治, 齋藤智彦

    第29回日本放射光学会年会・放射光科学合同シンポジウム  (柏の葉カンファレンスセンター) 

    Presentation date: 2016.01

  • 硬X線光電子分光法によるLa0.775Sr0.225-xCaxMn1-yGayO3の電子構造

    漆山翔, 大川万里生, 村上良明, 桑原英樹, 太刀川純孝, 齋藤智彦

    第29回日本放射光学会年会・放射光科学合同シンポジウム  (柏の葉カンファレンスセンター) 

    Presentation date: 2016.01

  • 光電子分光によるNd1-xSrxVO3の擬ギャップの観測

    山本紳太郎, 下中大也, 柴田大輔, 小寺健二朗, 吉田鉄平, 藤森淳, 大川万里生, 斎藤智彦, 組頭広志, 小野寛太, 池永英司, 宮坂茂樹, 田島節子

    日本物理学会2015年秋季大会  (関西大学北千里キャンパス) 

    Presentation date: 2015.09

  • Large Energy-scale ARPES Spectral Modulation with Temperature in a Layered Manganite

    N. Yoshizawa, Y. Maeda, M. Okawa, M. Akaki, D. Akahoshi, H. Kuwahara, Y. Aiura, Y. Kotani, M. Kubota, K. Ono, N. Hamada, T. Saitoh

    International Workshop on Strong Correlations and Angle-Resolved Photoemission Spectroscopy (CORPES15)  (Couvent des Cordeliers, Paris) 

    Presentation date: 2015.07

  • Angle-resolved Photoemission Study of a Thermoelectric and Multiferroic Delafossite CuCrO2

    R. Kato, M. Okawa, K. Ono, T. Okuda, T. Saitoh

    International Workshop on Strong Correlations and Angle-Resolved Photoemission Spectroscopy (CORPES15)  (Couvent des Cordeliers, Paris) 

    Presentation date: 2015.07

  • Valence-fluctuations and Peierls Metal-insulatro Transition in a Correlated Ferromagnet

    P. A. Bhobe, A. Kumar, M. Taguchi, R. Eguchi, M. Matsunami, Y. Takata, A. K. Nandy, P. Mahadevan, D. D. Sarma, A. Neroni, E. ?a?io?lu, M. Le?ai?, M. Oura, Y. Senba, H. Ohashi, K. Ishizaka, M. Okawa, S. Shin, K. Tamasaku, Y. Kohmura, M. Yabashi, T. Ishikawa, K. Hasegawa, M. Isobe, Y. Ueda, A. Chainani

    International Workshop on Strong Correlations and Angle-Resolved Photoemission Spectroscopy (CORPES15)  (Couvent des Cordeliers, Paris) 

    Presentation date: 2015.07

  • Direct Measurement of Non-equilibrium Electronic and Phonon Dynamics of Cu0.17Bi2Se3 via Time Resolved Photoemission Spectroscopy

    T. Yamamoto, Y. Ishida, R. Yoshida, M. Okawa, K. Okazaki, T. Kanai, A. Kikkawa, Y. Taguchi, T. Kiss, K. Ishizaka, N. Ishii, J. Itatani, S. Watanabe, Y. Tokura, T. Saitoh, S. Shin

    International Workshop on Strong Correlations and Angle-Resolved Photoemission Spectroscopy (CORPES15)  (Couvent des Cordeliers, Paris) 

    Presentation date: 2015.07

  • デラフォサイト型酸化物CuMO2 (M=Al,Cr,Fe)との比較によるクレドネライト型酸化物CuMnO2の電子構造

    加藤諒, 大川万里生, 和達大樹, 吉田鉄平, 小野寛太, 池永英司, 奥田哲治, 齋藤智彦

    日本物理学会第70回年次大会  (早稲田大学早稲田キャンパス) 

    Presentation date: 2015.03

  • SmB6の時間分解光電子分光:バルクギャップ形成とともに表面に現れる光起電力

    石田行章, 乙津聡夫, 島田智子, 大川万里生, 小林洋平, 伊賀文俊, 高畠敏郎, 辛埴

    日本物理学会第70回年次大会  (早稲田大学早稲田キャンパス) 

    Presentation date: 2015.03

  • 重い電子系Yb化合物の軟X線時間分解光電子分光

    大川万里生

    東大放射光アウトステーションH26年度播磨研究報告会  (姫路市) 

    Presentation date: 2015.02

  • CuMO2(M=Al, Cr, Mn, Fe)の電子構造

    加藤諒, 大川万里生, 和達大樹, 吉田鉄平, 小野寛太, 池永英司, 奥田哲治, 齋藤智彦

    第28回日本放射光学会年会・放射光科学合同シンポジウム  (立命館大学びわこ・くさつキャンパス) 

    Presentation date: 2015.01

  • LaCo1-xRhxO3の電子構造

    岡田陸, 田路智也, 大川万里生, 和達大樹, 吉田鉄平, 小林義彦, 寺門悠樹, 浅井吉蔵, 池永英司, 坂井延寿, 組頭広志, 浜田典昭, 齋藤智彦

    第28回日本放射光学会年会・放射光科学合同シンポジウム  (立命館大学びわこ・くさつキャンパス) 

    Presentation date: 2015.01

  • CuCrO2の電子構造と磁気特性・輸送特性の関係

    加藤諒, 大川万里生, 和達大樹, 吉田徹平, Kozina Xeniya, 池永英司, 小野寛太, 奥田哲治, 齋藤智彦

    第75回応用物理学会秋季学術講演会  (北海道大学札幌キャンパス) 

    Presentation date: 2014.09

  • デラフォサイト型酸化物CuMO2(M=Cr, Fe, Al)の電子構造

    加藤諒, 大川万里生, 小野寛太, 奥田哲治, 齋藤智彦, 池永英司, 和達大樹, 吉田鉄平, 浜田典昭

    日本物理学会2014年秋季大会  (中部大学春日井キャンパス) 

    Presentation date: 2014.09

  • LaCo1-xRhxO3の電子構造:HX-PESとバンド計算の比較

    岡田陸, 田路智也, 大川万里生, 和達大樹, 吉田鉄平, 小林義彦, 寺門悠樹, 浅井吉蔵, Xeniya Kozina, 池永英司, 坂井延寿, 組頭広志, 浜田典昭, 齋藤智彦

    日本物理学会2014年秋季大会  (中部大学春日井キャンパス) 

    Presentation date: 2014.09

  • Metal-to-insulator crossover in YbB12 seen via ultrahigh-resolution laser photoemission and time-resolved photoemission spectroscopy

    Mario Okawa, Yukiaki Ishida, Tomoko Shimada, Fumitoshi Iga, Toshiro Takabatake, Tomohiko Saitoh, Shik Shin

    International Conference on Strongly Correlated Electron Systemes (SCES2014)  (Campus Saint Martin d'H?res, Grenoble, France) 

    Presentation date: 2014.07

  • 光電子分光による擬三角格子系Ba2Ti13O22の電子構造の研究

    関根翔, 小嶋秀和, 大川万里生, 小野寛太, 孝山康太, 勝藤拓郎, 齋藤智彦

    日本物理学会第69回年次大会  (東海大学湘南キャンパス) 

    Presentation date: 2014.03

  • 光電子分光によるデラフォサイト型酸化物CuMO2(M=Al,Fe)の電子構造の研究

    加藤諒, 大川万里生, 和達大樹, 吉田鉄平, Xeniya Kozina, 池永英司, 小野寛太, 奥田哲治, 齋藤智彦

    日本物理学会第69回年次大会  (東海大学湘南キャンパス) 

    Presentation date: 2014.03

  • LaCo1-xRhxO3の光電子分光

    岡田陸, 田路智也, 大川万里生, 和達大樹, 吉田鉄平, 小林義彦, 寺門悠樹, 浅井吉蔵, Xeniya Kozina, 池永英司, 坂井延寿, 組頭広志, 仲武昌史, 生天目博文, 谷口雅樹, 齋藤智彦

    日本物理学会第69回年次大会  (東海大学湘南キャンパス) 

    Presentation date: 2014.03

  • 光電子分光によるLaCo1-xRhxO3の電子構造

    田路智也, 岡田陸, 長谷川敦, 大川万里生, 小林義彦, 寺門悠樹, 浅井吉蔵, 仲武昌史, 生天目博文, 谷口雅樹, 組頭広志, 小野寛太, 和達大樹, 山本周玄, 津山智之, 池永英司, 杉山武晴, 齋藤智彦

    第27回日本放射光学会年会・放射光科学合同シンポジウム  (広島国際会議場) 

    Presentation date: 2014.01

  • 宇宙機用放射率可変素子(SRD)の性能向上に関する研究―元素置換による放射特性の変化―

    田中洸輔, 太刀川純孝, 桑原英樹, 大川万里生, 齋藤智彦

    第34回日本熱物性シンポジウム  (富山県民会館) 

    Presentation date: 2013.11

  • 価数揺動系α-Yb(Al,Fe)B4におけるYb価数のFeドープ・温度依存性

    大川万里生, 笠原聡, 田路智也, 山村周玄, 和達大樹, 吉田鉄平, 杉山武晴, 池永英司, 田口宗孝, 辛埴, 久我健太郎, 中辻知, 齋藤智彦

    日本物理学会2013年秋季大会  (徳島大学) 

    Presentation date: 2013.09

  • Mn酸化物を用いた宇宙機用放射率可変素子(SRD)の開発(2)

    田中洸輔, 太刀川純孝, 桑原英樹, 大川万里生, 齋藤智彦

    日本物理学会2013年秋季大会  (徳島大学) 

    Presentation date: 2013.09

  • Electronic structure evolution of La0.6Sr0.4Mn1-yNbyO3 across a metal-insulator transition by Nb doping

    T. Hishida, K. Ohbayashi, M. Okawa, T. Saitoh

    The International Conference on Strongly Correlated Electron Systems (SCES2013)  (University of Tokyo, Tokyo, Japan) 

    Presentation date: 2013.08

  • Cu-O-Cr hybridization effects on the electronic structure of a hole-doped delafossite oxide CuCr1-xMgxO2

    M. Okawa, T. Yokobori, K. Konishi, R. Takei, K. Katayama, S. Oozono, T. Shinmura, T. Okuda, H. Wadati, E. Sakai, H. Kumigashira, M. Oshima, T. Sugiyama, E. Ikenaga, N. Hamada, T. Saitoh

    The International Conference on Strongly Correlated Electron Systems (SCES2013)  (University of Tokyo, Tokyo, Japan) 

    Presentation date: 2013.08

  • A self-emissivity-controlling radiator for spacecrafts by making use of a metal-insulator transition in magnetoresistive manganites

    K. Tanaka, S. Tachikawa, H. Kuwahara, M. Okawa, T. Saitoh

    The 12th Asia Pacific Physics Conference of AAPPS (APPC12)  (Makuhari Messe, Chiba, Japan) 

    Presentation date: 2013.07

  • Buried well-screened state in photoemission spectra of La1-xSrxMnO3

    T. Hishida, K. Ohbayashi, M. Kobata, E. Ikenaga, T. Sugiyama, K. Kobayashi, M. Okawa, T. Saitoh

    The 12th Asia Pacific Physics Conference of AAPPS (APPC12)  (Makuhari Messe, Chiba, Japan) 

    Presentation date: 2013.07

  • 光電子分光・軟X線吸収分光によるCuCr1-xMgxO2の電子構造

    小西康太, 横堀巧, 大川万里生, 武井亮太, 片山和哉, 大園怜, 新村崇, 奥田哲治, 和達大樹, 尾嶋正治, 坂井延寿, 小野寛太, 組頭広志, 杉山武晴, 池永英司, 浜田典昭, 齋藤智彦

    日本物理学会第68回年次大会  (広島大学) 

    Presentation date: 2013.03

  • Mn酸化物を用いた宇宙機用放射率可変素子(SRD)の開発

    田中洸輔, 太刀川純孝, 桑原英樹, 大川万里生, 齋藤智彦

    第60回応用物理学会春季学術講演会  (神奈川工科大学) 

    Presentation date: 2013.03

  • 高分解能角度分解光電子分光によるディラック電子系の量子現象の解明

    高橋隆, 中山耕輔, 菅原克明, 相馬清吾, 佐藤宇史, 吉田鉄平, 藤森淳, 大川万里生, 齋藤智彦, 小野寛太, 組頭広志

    第30回PFシンポジウム  (つくば国際会議場) 

    Presentation date: 2013.03

  • Mn酸化物を用いた宇宙機用放射率可変素子(SRD)の開発

    田中洸輔, 太刀川純孝, 桑原英樹, 大川万里生, 齋藤智彦

    日本物理学会2012年秋季大会  (横浜国立大学) 

    Presentation date: 2012.09

  • X-Ray Absorption Spectroscopy of Double-Perovskite Co Oxides with High-Spin Configuration

    M. Okawa, A. Hasegawa, H. Wadati, K. Takubo, T. Mizokawa, T. Z. Regier, Y. Kobayashi, Y. Terakado, N. Arai, K. Asai, T. Saitoh

    12th International Conference on Electron Spectroscopy and Structure (ICESS-12)  (Le Grand Large, Saint-Malo, France) 

    Presentation date: 2012.09

  • 二重ペロブスカイト型Co酸化物のX線吸収分光

    大川万里生, 長谷川敦, 西村淳一, 和達大樹, 田久保耕, 溝川貴司, Tom Z. Regier, 小林義彦, 寺門悠樹, 新井伸英, 浅井吉蔵, 齋藤智彦

    日本物理学会第67回年次大会  (関西学院大学) 

    Presentation date: 2012.03

  • Sr3Fe2-xCoxO7-δの光電子分光

    内藤理恵, 中野裕太, 大川万里生, 和達大樹, 中村亮太, 戸澤純一郎, 赤木暢, 桑原英樹, 杉山武晴, 池永英司, 小野寛太, 組頭広志, 齋藤智彦

    日本物理学会第67回年次大会  (関西学院大学) 

    Presentation date: 2012.03

  • Mgドープによるデラフォサイト型酸化物CuCr1-xMgxO2の電子構造の変化

    横堀匠, 小西康太, 武井亮太, 片山和哉, 大川万里生, 齋藤智彦, 大園怜, 新村崇, 奥田哲治, 和達大樹, 杉山武晴, 池永英司, 小野寛太, 浜田典昭

    日本物理学会第67回年次大会  (関西学院大学) 

    Presentation date: 2012.03

  • 円二色性ARPESで見るSrTiO3とCuxBi2Se3の表面電子状態

    石田行章, 菅藤裕昭, 吉川明子, 田口康二郎, 伊藤孔明, 大田由一, 岡崎浩三, Walid Malaeb, Mattia Mulazzi, 大川万里生, 渡部俊太郎, Chuangtian Chen, 金民祐, Christopher Bell, 小塚裕介, Harold, Y. Hwang, 十倉好紀, 辛埴

    日本物理学会第67回年次大会  (関西学院大学) 

    Presentation date: 2012.03

  • 光電子分光法によるCuCr1-xMgxO2の電子構造

    横堀匠, 小西康太, 武井亮太, 片山和哉, 大川万里生, 大園怜, 新村崇, 奥田哲治, 小野寛太, 組頭広志, 浜田典昭, 和達大樹, 池永英司, 杉山武晴, 齋藤智彦

    第29回PFシンポジウム  (つくば国際会議場エポカル) 

    Presentation date: 2012.03

  • 光電子分光法によるCuCr1-xMgxO2の電子構造

    横堀匠, 小西康太, 武井亮太, 片山和哉, 大川万里生, 齋藤智彦, 大園怜, 新村崇, 奥田哲治, 浜田典昭, 小野寛太, 和達大樹, 池永英司, 杉山武晴

    第25回日本放射光学会年会  (鳥栖市民文化会館・中央公民館) 

    Presentation date: 2012.01

  • 光電子分光法によるデラフォサイト型酸化物CuCr1-xMgxO2の電子構造

    横堀匠, 小西康太, 武井亮太, 片山和哉, 大川万里生, 齋藤智彦, 大園怜, 新村崇, 奥田哲治, 浜田典昭, 小野寛太, 和達大樹, 杉山武晴, 池永英司

    日本物理学会2011年秋季大会  (富山大学) 

    Presentation date: 2011.09

  • レーザー光電子分光によるデツインされたBaFe2As2の電子状態の研究2

    園部竜也, 下志万貴博, 坂野昌人, 大川万里生, ワリッドマラエブ, 富樫格, 渡部俊太郎, 辛埴, 石田茂之, 中島正道, 内田慎一, 富岡泰秀, 木方邦宏, 李哲虎, 伊豫彰, 永崎洋, 伊藤利充, 石坂香子

    日本物理学会2011年秋季大会  (富山大学) 

    Presentation date: 2011.09

  • 光電子分光法による二重ペロブスカイト型Co酸化物の電子構造

    長谷川敦, 西村淳一, 齋藤智彦, 大川万里生, 小林義彦, 寺門悠樹, 新井伸英, 浅井吉蔵, 浜田典明, 仲武昌史, 姜健, 島田賢也, 生天目博文, 谷口雅樹, 上田茂典, 山下良之, 吉川英樹, 小林啓介

    日本物理学会2011年秋季大会  (富山大学) 

    Presentation date: 2011.09

  • 時間分解光電子分光によるSmB6の近藤ギャップ観測

    島田智子, 石田行章, 松波雅治, 大川万里生, 伊賀文俊, 高畠敏郎, A. Chainani, Chuang-Tian Chen, 渡部俊太郎, 辛埴

    日本物理学会2011年秋季大会  (富山大学) 

    Presentation date: 2011.09

  • 時間分解光電子分光から見た近藤半導体YbB12の混成ギャップ形成II

    大川万里生, 石田行章, 島田智子, 伊賀文俊, 高畠敏郎, Chuang-Tian Chen, 渡部俊太郎, 辛埴

    日本物理学会2011年秋季大会  (富山大学) 

    Presentation date: 2011.09

  • Co 3d Spin Configuration in Double-Perovskite-Type Cobaltates Studied by X-Ray Absorption Spectroscopy

    M. Okawa, H. Hasegawa, J. Nishimura, H. Wadati, K. Takubo, T. Mizokawa, T. Regier, Y. Kobayashi, Y. Terakado, N. Arai, K. Asai, T. Saitoh

    PF研究会「軟X線分光・散乱測定を用いた物性研究の現状と展望」  (高エネルギー加速器研究機構) 

    Presentation date: 2011.09

  • Photoemission spectroscopy of delafossite oxide CuCr1-xMgxO2

    T. Yokobori, K. Konishi, R. Takei, K. Katayama, M. Okawa, T. Saitoh, S. Oozono, T. Shinmura, T. Okuda, N. Hamada, K. Ono, H. Wadati, T. Sugiyama, E. Ikenaga

    フォトンファクトリー研究会「軟X線分光・散乱測定を用いた物性研究の現状と展望」  (高エネルギー加速器研究機構) 

    Presentation date: 2011.09

  • Search for Spectroscopic Signatures of Hidden Order in URu2Si2

    R. Yoshida, M. Fukui, Y. Haga, E. Yamamoto, Y. Onuki, M. Okawa, W. Malaeb, S. Shin, M. Hirai, Y. Muraoka, T. Yokoya

    International Conference on Strongly Correlated Electron Systems (SCES) 2011  (Cambridge, UK) 

    Presentation date: 2011.09

  • URu2Si2の超高分解能ARPES:光電子スペクトルに見られる微細構造

    吉田力矢, 福井仁紀, 芳賀芳範, 山本悦嗣, 大貫惇睦, 大川万里生, Walid Malaeb, 辛埴, 平井正明, 村岡祐治, 横谷尚睦

    日本物理学会第66回年次大会  (新潟大学) 

    Presentation date: 2011.03

  • 時間分解光電子分光から見た近藤半導体YbB12の混成ギャップ形成

    大川万里生, 石田行章, 島田智子, 伊賀文俊, 高畠敏郎, Chuang-Tian Chen, 渡部俊太郎, 辛埴

    日本物理学会第66回年次大会  (新潟大学) 

    Presentation date: 2011.03

  • レーザー光電子分光によるデツインされたBaFe2As2の電子状態の研究

    園部竜也, 下志万貴博, 坂野昌人, 大川万里生, ワリッドマラエブ, 富樫格, 渡部俊太郎, 辛埴, 中島正道, 石田茂之, 内田慎一, 富岡泰秀, 木方邦宏, 李哲虎, 伊豫彰, 永崎洋, 伊藤利充, 石坂香子

    日本物理学会第66回年次大会  (新潟大学) 

    Presentation date: 2011.03

  • 不足ドープBi2(Sr,La)2CuO6+δの超伝導ギャップのキャリア濃度依存性

    小川古都, 洪辰杓, 竹内恒博, 大川万里生, Walid Malaeb,辛埴

    日本物理学会第66回年次大会  (新潟大学) 

    Presentation date: 2011.03

  • 重い電子系価揺動物質α-YbAlB4の鉄ドープ誘起の磁性と価数変化

    久我健太郎, 松本洋介, 中辻知, 大川万里生, 高田恭孝, 松波雅治, 江口律子, 田口宗孝, Ashish Chainani, 辛埴, 西野吉則, 玉作賢治, 矢橋牧名, 石川哲也, 木内陽子

    日本物理学会第66回年次大会  (新潟大学) 

    Presentation date: 2011.03

  • Laser angle resolved photoemission study on superconducting iron pnictides of BaFe2As2 family

    T. Shimojima, F. Sakaguchi, K. Ishizaka, Y. Ishida, T. Kiss, M. Okawa, S. Watanabe, K. Ohgushi, S. Shin, T. Togashi, A. Chainani, C.-T. Chen, M. Arita, K. Shimada, H. Namatame, M. Taniguchi, T. Terashima, T. Shibauchi, Y. Matsuda

    International Workshop on Novel Superconductors and Super Materials 2011  (National Museum of Emerging Science and Innovation (Miraikan), Tokyo) 

    Presentation date: 2011.03

  • YbAlB4系における Yb 価数と量子臨界現象

    大川万里生

    新学術領域研究「重い電子系の形成と秩序化」ワークショップ 〜Yb系重い電子化合物における電子状態と新しい物性〜  (姫路商工会議所) 

    Presentation date: 2011.01

  • URu2Si2のレーザー角度分解光電子分光II

    吉田力矢, 中村祥明, 福井仁紀, 芳賀芳範, 山本悦嗣, 大貫惇睦, 大川万里生, 辛埴, 平井正明, 村岡祐治, 横谷尚睦

    日本物理学会2010年秋季大会  (大阪府立大学) 

    Presentation date: 2010.09

  • 充填スクッテルダイト超伝導体RPt4Ge12(R=La,Pr)の電子状態

    中村祥明, 岡崎宏之, 吉田力矢, 脇田高徳, 平井正明, 村岡祐治, 竹屋浩幸, 平田和人, 大川万里生, 辛埴, 渡部俊太郎, C.-T.Chen, 組頭広志, 尾嶋正治, 横谷尚睦

    日本物理学会2010年秋季大会  (大阪府立大学) 

    Presentation date: 2010.09

  • NaFeAsのレーザー角度分解光電子分光

    岡崎浩三, 大川万里生, 目崎雄二, 北川健太郎, 松林和幸, 瀧川仁, 上床美也, 渡部俊太郎, C.T.Chen,辛埴

    日本物理学会2010年秋季大会  (大阪府立大学) 

    Presentation date: 2010.09

  • Laser Angle-Resolved Photoemission on URu2Si2

    R. Yoshida, Y. Nakamura, M. Fukui, Y. Haga, E. Yamamoto, Y. Onuki, M. Okawa, S. Shin, M. Hirai, Y. Muraoka, T. Yokoya

    International Conference on Heavy Electrons 2010  (Tokyo Metropolitan University, Tokyo) 

    Presentation date: 2010.09

  • Valence fluctuation in the heavy fermion YbAlB4 system studied by hard x-ray photoemission spectroscopy

    M. Okawa, M. Matsunami, K. Kuga, K. Ishizaka, R. Eguchi, M. Taguchi, A. Chainani, Y. Takata, M. Yabashi, K. Tamasaku, Y. Nishino, T. Ishikawa, N. Horie, S. Nakatsuji, S. Shin

    37th International Conference on Vacuum Ultraviolet and X-Ray Physics  (University of British Columbia, Vancouver) 

    Presentation date: 2010.07

  • Laser ARPES Study of the Hidden-Order State in URu2Si2

    R. Yoshida, Y. Nakamura, M. Fukui, Y. Haga, E. Yamamoto, Y. Onuki, M. Okawa, S. Shin, M. Hirai, Y. Muraoka, T. Yokoya

    International Conference on Strongly Correlated Electron Systems  (Santa Fe, USA) 

    Presentation date: 2010.06

  • Ultrahigh-Resolution Photoemission Study of URu2Si2 across the Hidden Order Transition

    R. Yoshida, Y. Nakamura, M. Fukui, Y. Haga, E. Yamamoto, Y. Onuki, M. Okawa, S. Shin, M. Hirai, Y. Muraoka, T. Yokoya

    The 9th International Conference on Spectroscopies in Novel Superconductors  (Shanghai, China) 

    Presentation date: 2010.05

  • レーザー角度分解光電子分光によるFeSe1-x(Tex)の超伝導電子状態の観測

    伊藤孔明, 下志万貴博, 石坂香子, 大川万里生, 木須孝幸, 渡部俊太郎, 新高誠司, 花栗哲郎, 高木英典, Y.Wang, C.T.Chen,辛埴

    日本物理学会第65回年次大会  (岡山大学) 

    Presentation date: 2010.03

  • URu2Si2のレーザー角度分解光電子分光

    吉田力矢, 中村祥明, 福井仁紀, 芳賀芳範, 山本悦嗣, 大貫惇睦, 大川万里生, 辛埴, 渡部俊太郎, C.T. Chen, 平井正明, 村岡祐治, 横谷尚睦

    日本物理学会第65回年次大会  (岡山大学) 

    Presentation date: 2010.03

  • 不足ドープBi2(Sr,La)2CuO6+δの超伝導ギャップのキャリア濃度依存性

    小川古都, 浜谷陽一郎, 竹内恒博, 大川万里生, 石坂香子, 辛埴

    日本物理学会第65回年次大会  (岡山大学) 

    Presentation date: 2010.03

  • FeSeの電子状態における置換効果II

    津田俊輔, 水口佳一, 山口尚秀, 高野義彦, 大川万里生, 石田行章, 石坂香子, 辛埴, 渡部俊太郎, C.-T. Chen

    日本物理学会第65回年次大会  (岡山大学) 

    Presentation date: 2010.03

  • 充填スクッテルダイト超伝導体PrPt4Ge12の超高分解能レーザー光電子分光による超伝導ギャップ測定

    中村祥明, 岡崎宏之, 吉田力矢, 脇田高徳, 平井正明, 村岡祐治, 竹屋浩幸, 平田和人, 大川万里生, 辛埴, 渡部俊太郎, C.-T.Chen, 組頭広志, 尾嶋正治, 横谷尚睦

    日本物理学会第65回年次大会  (岡山大学) 

    Presentation date: 2010.03

  • 鉄系超伝導体KFe2As2のレーザー角度分解光電子分光

    大田由一, 下志万貴博, 石坂香子, 大川万里生, 木須孝幸, Y.Wang, C.T.Chen, 渡辺俊太郎, 木方邦宏, 李哲虎, 伊豫彰, 永崎洋, 齊藤拓, 深澤英人, 小堀洋,辛埴

    日本物理学会第65回年次大会  (岡山大学) 

    Presentation date: 2010.03

  • レーザー角度分解光電子分光による鉄系超伝導体BaFe2(As1-xPx)2のフェルミ面及び超伝導ギャップ観測II

    坂口文規, 下志万貴博, 石坂香子, 石田行章, 大川万里生, 木須孝幸, 富樫格, X.-Y.Wang, C.T.Chen, 渡部俊太郎, 笠原成, 芝内孝禎, 松田祐司, 竹屋浩幸, 平田和人, 寺嶋孝仁, 辛埴

    日本物理学会第65回年次大会  (岡山大学) 

    Presentation date: 2010.03

  • 不足ドープ(Bi,Pb)2(Sr,La)2CuO6+δにおける準粒子の寿命の方位依存性と温度依存性

    浜谷陽一郎, 小川古都, 竹内恒博, 大川万里生, 石坂香子, 辛埴

    日本物理学会第65回年次大会  (岡山大学) 

    Presentation date: 2010.03

  • バルク敏感光電子分光によるYbAlB4の研究

    大川万里生, 松波雅治, 石坂香子, 江口律子, 田口宗孝, Ashish Chainani, 高田恭孝, 矢橋牧名, 玉作賢治, 西野吉則, 石川哲也, X.-Y. Wang, C.-T. Chen, 渡部俊太郎, 久我健太郎, 堀江直樹, 中辻知,辛埴

    新学術領域研究「重い電子系の形成と秩序化」ワークショップ 〜先端光電子分光による重い電子系研究〜  (岡山大学) 

    Presentation date: 2009.12

  • 重い電子系Yb(Al,Fe)B4におけるYb価数のFe置換依存性

    大川万里生, 松波雅治, 石坂香子, 江口律子, 田口宗孝, Ashish Chainani, 高田恭孝, 矢橋牧名, 玉作賢治, 西野吉則, 石川哲也, 久我健太郎, 堀江直樹, 中辻知,辛埴

    日本物理学会2009年秋季大会  (熊本大学) 

    Presentation date: 2009.09

  • 充填スクッテルダイト化合物PrPt4Ge12超伝導体の光電子分光

    中村祥明, 岡崎宏之, 吉田力矢, 脇田高徳, 平井正明, 村岡祐治, 竹屋浩幸, 平田和人, 大川万里生, 辛埴, 渡部俊太郎, C.-T.Chen, 組頭広志, 尾嶋正治, 横谷尚睦

    日本物理学会2009年秋季大会  (熊本大学) 

    Presentation date: 2009.09

  • レーザー角度分解光電子分光による鉄系超伝導体PrFeAsO1-yのフェルミ面・超伝導ギャップ観測

    坂口文規, 下志万貴博, 石田行章, 大川万里生, 石坂香子, 木須孝幸, 渡辺俊太郎, Y.Wang, C.T.Chen, 石角元志, 伊豫彰, 木方邦宏, 鬼頭聖, 永崎洋, 社本真一, 辛埴

    日本物理学会2009年秋季大会  (熊本大学) 

    Presentation date: 2009.09

  • (BaK)Fe2As2のレーザー角度分解光電子分光II:超伝導ギャップ対称性と擬ピークの起源

    下志万貴博, 坂口文規, 石坂香子, 石田行章, 大川万里生, 木須孝幸, 渡部俊太郎, Y.Wang, C.T.Chen, 片山尚幸, 大串研也, 辛埴

    日本物理学会2009年秋季大会  (熊本大学) 

    Presentation date: 2009.09

  • FeSeの電子状態における置換効果

    津田俊輔, 水口佳一, 山口尚秀, 高野義彦, 大川万里生, 石田行章, 石坂香子, 辛埴, 渡部俊太郎, C.-T. Chen

    日本物理学会2009年秋季大会  (熊本大学) 

    Presentation date: 2009.09

  • Strong Kondo screening near the quantum critical point in heavy fermon superconductor β-YbAlB4 studied by hard x-ray photoemission spectroscopy

    M. Okawa, M. Matsunami, K. Ishizaka, R. Eguchi, M. Taguchi, A. Chainani, Y. Takata, M. Yabashi, K. Tamasaku, Y. Nishino, T. Ishikawa, K. Kuga, N. Horie, S. Nakatsuji, S. Shin

    9th International Conference on Materials and Mechanisms of Superconductivity  (Keio Plaza Hotel, Tokyo) 

    Presentation date: 2009.09

  • Bulk-sensitive laser-ARPES study on the cuprate superconductor YBa2Cu3O7?δ

    M. Okawa, K. Ishizaka, T. Kiss, T. Shimojima, T. Togashi, S. Watanabe, T. Masui, S. Tajima, A. Chainani, T. Saitoh, S. Shin

    9th International Conference on Materials and Mechanisms of Superconductivity  (Keio Plaza Hotel, Tokyo) 

    Presentation date: 2009.09

  • Photoemission Study on Superconducting FeSe

    R. Yoshida, T. Wakita, H. Okazaki, Y. Mizuguchi, S. Tsuda, Y. Takano, H. Takeya, K. Hirata, Y. Kato, T. Muro, M. Okawa, K. Ishizaka, S. Shin, H. Harima, M. Hirai, Y. Muraoka, T. Yokoya

    9th International Conference on Materials and Mechanisms of Superconductivity  (Keio Plaza Hotel, Tokyo) 

    Presentation date: 2009.09

  • レーザー角度分解光電子分光によるBaFe2As2のフェルミ面観測

    下志万貴博, 石田行章, 石坂香子, 片山尚幸, 大串研也, 木須孝幸, 大川万里生, 富樫格, X.-Y. Wang, C.-T. Chen, 渡部俊太郎, 小口多美夫, 辛埴

    日本物理学会 第64回年次大会  (立教大学) 

    Presentation date: 2009.03

  • レーザー角度分解光電子分光による鉄系超伝導体(Ba0.6K0.4)Fe2As2の電子状態の直接観測

    坂口文規, 下志万貴博, 石田行章, 大川万里生, 石坂香子, 木須孝幸, 渡辺俊太郎, Y.Wang, C.T.Chen, 片山尚幸, 大串研也, 辛埴

    日本物理学会第64回年次大会  (立教大学) 

    Presentation date: 2009.03

  • 重い電子系YbAlB4の光電子分光:電子構造と価数評価

    大川万里生, 松波雅治, 石坂香子, 江口律子, 田口宗孝, Ashish Chainani, 高田恭孝, 矢橋牧名, 玉作賢治, 西野吉則, 石川哲也, 久我健太郎, 堀江直樹, 中辻知,辛埴

    日本物理学会第64回年次大会  (立教大学) 

    Presentation date: 2009.03

  • FeSe超伝導体の電子状態

    吉田力矢, 脇田高徳, 岡崎宏之, 水口佳一, 津田俊輔, 高野義彦, 竹屋浩幸, 平田和人, 室隆桂之, 大川万里生, 石坂香子, 辛埴, 播磨尚朝, 平井正明, 村岡祐治, 横谷尚睦

    日本物理学会第64回年次大会  (立教大学) 

    Presentation date: 2009.03

  • FeSe関連物質における高分解能光電子分光

    津田俊輔, 水口佳一, 冨岡史明, 山口尚秀, 高野義彦, 大川万里生, 石田行章, 石坂香子, 辛埴, 渡部俊太郎, C.-T. Chen

    日本物理学会第64回年次大会  (立教大学) 

    Presentation date: 2009.03

  • Fermi surface of the parent compound of iron-based superconductor

    T. Shimojima, Y. Ishida, N. Katayama, K. Ohgushi, K. Ishizaka, T. Kiss, M. Okawa, T. Togashi, X.-Y. Wang, C.-T. Chen, S. Watanabe, T. Oguchi, S. Shin

    2009 APS March Meeting  (Pittsburgh, Pennsylvania) 

    Presentation date: 2009.03

  • Unusual pseudogap features observed in iron-oxypnictide superconductors

    Y. Ishida, T. Shimojima, K. Ishizaka, T. Kiss, M. Okawa, T. Togashi, S. Watanabe, X.-Y. Wang, C.-T. Chen, Y. Kamihara, M. Hirano, H. Hosono, S. Shin

    2009 APS March Meeting  (Pittsburgh, Pennsylvania) 

    Presentation date: 2009.03

  • Electronic Structure of Superconducting FeSe Studied by Photoemission Spectroscopy

    Rikiya Yoshida, Takanori Wakita, Hiroyuki Okazaki, Yoshikazu Mizuguchi, Shunsuke Tsuda, Yoshihiko Takano, Hiroyuki Takeya, Kazuto Hirata, Takayuki Muro, Mario Okawa, Kyoko Ishizaka, Shik Shin, Hisatomo Harima, Masaaki Hirai, Yuji Muraoka, Takayoshi Yokoya

    2009 APS March Meeting  (Pittsburgh, Pennsylvania) 

    Presentation date: 2009.03

  • レーザーARPESによる高温超伝導体YBa2Cu3O7?δの超伝導電子状態の観測

    大川万里生, 石坂香子, 内山裕士, 只友浩貴, 増井孝彦, 田島節子, Xiaoyang Wang, Chuangtian Chen, 渡部俊太郎, Ashish Chainani, 齋藤智彦, 辛埴

    PF研究会「高分解能角度分解光電子分光研究と将来展望」  (高エネルギー加速器研究機構) 

    Presentation date: 2008.12

  • Sm1.85Ce0.15CuO4のレーザー励起角度分解光電子分光

    池田正樹, Andres Felipe Santander-Syro, 吉田鉄平, 藤森淳, Nicole Bontemps, 大川万里生, 石坂香子, 木須孝幸, 辛埴,Alexandre Zimmers,Bing Liang, Pengcheng Li, Rick Greene

    日本物理学会2008年秋季大会  (岩手大学) 

    Presentation date: 2008.09

  • La1.85Sr0.15CuO4のレーザー励起角度分解光電子分光

    吉田鉄平, Walid Malaeb, 池田正樹, 藤森淳, 大川万里生, 木須孝幸, 石坂香子, 辛埴, 小宮世紀, 安藤陽一, 永崎洋, 内田慎一

    日本物理学会2008年秋季大会  (岩手大学) 

    Presentation date: 2008.09

  • YBa2Cu3O7-δにおけるバルク電子構造の温度依存性:レーザー励起角度分解光電子分光による測定

    大川万里生, 石坂香子, 木須孝幸, 下志万貴博, 富樫格, 渡部俊太郎, X.-Y. Wang, C.-T. Chen, 内山裕士, 増井孝彦, 田島節子, 齋藤智彦, 辛埴

    日本物理学会2008年秋季大会  (岩手大学) 

    Presentation date: 2008.09

  • Na0.7CoO2の広温度領域における準粒子特性

    下志万貴博, 石坂香子, 木須孝幸, 大川万里生, 富樫格, X.-Y.Wang, C.T.Chen, P.Badica, 山田和芳, 戸叶一正, 渡部俊太郎, 埴

    日本物理学会2008年秋季大会  (岩手大学) 

    Presentation date: 2008.09

  • Bi2(Sr,R)2CuOyにおけるノード近傍の電子状態のR依存性II

    川口昂彦, 岡田佳憲, 竹内恒博, 大川万里生, 石坂香子, 辛埴, 生田博志

    日本物理学会2008年秋季大会  (岩手大学) 

    Presentation date: 2008.09

  • Fe系高温超伝導体のレーザー光電子分光

    石田行章, 下志万貴博, 石坂香子, 木須孝幸, 大川万里生, 富樫格, 渡部俊太郎, X.-Y. Wang, C.-T. Chen, 神原陽一, 平野正浩, 細野秀雄, 辛埴

    日本物理学会2008年秋季大会  (岩手大学) 

    Presentation date: 2008.09

  • Bi2(Sr, R)2CuOyにおけるノード近傍の電子状態のR依存性

    岡田佳憲, 竹内恒博, 石坂香子, 大川万里生, 下山田篤史, 辛埴, 生田博志

    日本物理学会第63回年次大会  (近畿大学) 

    Presentation date: 2008.03

  • 鉄珪化物超伝導体Lu2Fe3Si5のバルク光電子分光

    馬場輝久, 松波雅治, 江口律子, 石田行章, A.Chainani, 大川万里生, 石坂香子, 木須孝幸, 下志万貴博, 笹目大樹, 渡辺忠孝, 高野良紀, 仙波泰徳, 大橋治彦, 富樫格, 渡辺俊太郎, X.-Y. Wang, C.T. Chen, 辛埴

    日本物理学会第63回年次大会  (近畿大学) 

    Presentation date: 2008.03

  • YBa2Cu3O7-δのレーザー励起角度分解光電子分光III

    大川万里生, 石坂香子, 木須孝幸, 下志万貴博, 富樫格, 渡部俊太郎, X, Y. Wang, C. T. Chen, 内山裕士, 増井孝彦, 田島節子, 齋藤智彦, 辛埴

    日本物理学会第62回年次大会  (北海道大学) 

    Presentation date: 2007.09

  • VUV laser-excited angle-resolved photoemission study on the superconducting state in YBa2Cu3O7?δ

    M. Okawa, K. Ishizaka, T. Kiss, T. Shimojima, T. Togashi, S. Watanabe, H. Uchiyama, T. Masui, S. Tajima, T. Saitoh, S. Shin

    15th International Conference on Vacuum Ultraviolet Radiation Physics  (Konzerthaus Berlin, Berlin) 

    Presentation date: 2007.07

  • レーザー励起角度分解光電子分光によるYBa2Cu3O7-δのバルク電子状態の研究

    大川万里生, 石坂香子, 木須孝幸, 下志万貴博, 富樫格, 渡部俊太郎, 齋藤智彦, 内山裕士, 増井孝彦, 田島節子, 辛埴

    日本物理学会2007年春季大会  (鹿児島大学) 

    Presentation date: 2007.03

  • YBa2Cu3O7-δのレーザー励起角度分解光電子分光

    大川万里生, 石坂香子, 木須孝幸, 下志万貴博, 齋藤智彦, 富樫格, 渡部俊太郎, C.Q. Zhang, C.T. Chen, 内山裕士, 増井孝彦, 田島節子, 辛埴

    日本物理学会2006年秋季大会  (千葉大学) 

    Presentation date: 2006.09

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Syllabus

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Teaching Experience

  • 卒業研究

    東京理科大学  

  • 応用物理特別講義4(振動・波動)

    東京理科大学  

  • 電磁気学1演習

    東京理科大学  

  • 応用物理学実験

    東京理科大学  

  • 量子力学1演習

    東京理科大学  

 

Committee Memberships

  • 2018.10
    -
    2019.09

    日本物理学会  領域8(強相関電子系分野)運営委員

  • 2016.04
    -
    2018.03

    高エネルギー加速器研究機構  PFニュース編集委員