Updated on 2024/05/16

写真a

 
SAWA Hiroshi
 
Organization
Graduate School of Engineering Applied Physics 2 Professor
Graduate School
Graduate School of Engineering
Undergraduate School
School of Engineering Physical Science and Engineering
Title
Professor
Contact information
メールアドレス

Degree 1

  1. 理学博士 ( 1990.3   青山学院大学 ) 

Research Interests 7

  1. 電子密度解析

  2. 構造物性研究

  3. 放射光X線回折

  4. X-ray diffraction/scattering

  5. structure analysis

  6. Structural Material Physics

  7. Synchrotron Radiation X-ray

Research Areas 2

  1. Others / Others  / Physical Properties II

  2. Natural Science / Magnetism, superconductivity and strongly correlated systems

Current Research Project and SDGs 1

  1. Study of Structural Material Science using Synchrotron X-ray diffraction

Research History 10

  1. Nagoya University   Graduate School of Engineering Applied Physics 2   Professor

    2017.4

  2. Nagoya University   Graduate School of Engineering Applied Physics 2   Professor

    2017.4

  3. Nagoya University   Professor

    2008.4 - 2017.3

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    Country:Japan

  4. Nagoya University   Graduate School of Engineering Department of Materials,Physics and Energy Engineering   Professor

    2008.4 - 2017.3

  5. 高エネルギー加速器研究機構   物質構造科学研究所   教授

    2005.5 - 2008.3

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    Country:Japan

  6. The Graduate University for Advanced Studies   Professor

    2005.5 - 2008.3

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    Country:Japan

  7. 高エネルギー加速器研究機構   物質構造科学研究所   准教授

    2001.10 - 2005.4

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    Country:Japan

  8. The Graduate University for Advanced Studies   Associate professor

    2001.10 - 2005.4

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    Country:Japan

  9. Chiba University   Associate professor

    1996.4 - 2001.9

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    Country:Japan

  10. The University of Tokyo   Assistant Professor

    1991.4 - 1996.3

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    Country:Japan

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Professional Memberships 8

  1. 日本物理学会   理事 (201503~202103)

    1985

  2. 日本放射光学会   評議員・幹事(2005~2009)

    2005

  3. 日本化学会

    1991.3

  4. 日本結晶学会

    1985

  5. THE CRYSTALLOGRAPHIC SOCIETY OF JAPAN

  6. THE PHYSICAL SOCIETY OF JAPAN

  7. THE JAPANESE SOCIETY FOR SYNCHROTRON RADIATION RESEARCH

  8. THE CHEMICAL SOCIETY OF JAPAN

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Committee Memberships 4

  1. 日本物理学会   理事  

    2016.3 - 2021.3   

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    Committee type:Academic society

  2. 東京大学物性研究所   協議会委員  

    2020.9 - 2022.8   

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    Committee type:Other

  3. 日本物理学会   理事  

    2016.4   

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    Committee type:Academic society

  4. 日本放射光学会   評議員  

    2003.1 - 2009.12   

Awards 3

  1. 日本物理学会第26回論文賞

    2021.3   日本物理学会   Superconductivity in Ca1-xLaxFeAs2: A Novel 112-Type Iron Pnictide with Arsenic Zigzag Bonds

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    Award type:Honored in official journal of a scientific society, scientific journal  Country:Japan

    2008年に細野らのグループによって発見された鉄ヒ素系超伝導体は、当初の超伝導転移温度は20K台であったものの、またたく間に世界中で類似構造物質が作製され、最高Tcは55Kにまで上昇した。その後の鉄化合物の新超伝導体探索は、転移温度上昇を狙ったものだけではなく、次元性と超伝導機構の関係を探るためにスペーサー層(FeAs層間の層)を厚くして3d電子系の2次元性を高めた物質開発などの研究が行われてきた。
     本論文は、ヒ素のジグザグ1次元鎖をスペーサー層とする新しい新超伝導体発見の論文である。その特徴は(i)他の鉄系超伝導体とは異なり単斜晶であること、(ii)1価のAs-がdimerを組んでいる1次元ジグザグ構造がFeAs層間にあること、(iii)鋭い超伝導転移は34Kで観測されたが、組成を最適化すれば45Kになりうる兆候が見えること、である。
     鉄系超伝導体の発見当初から、Ca-La-Fe-Asの4元系で超伝導の兆候が見られることは知られていたが、その結晶構造及び組成は不明であった。本論文は、理論予言されていた物質を合成してみせ、その謎に明確な答えを与えるものとなった。また、良質な単結晶を作製し、SPring-8のX線回折実験でのMEM解析によって電子密度分布を決定し、第一原理計算でフェルミ面形状を計算するなど、丁寧で良質な実験研究である点も、単なる新超伝導体発見の論文とは一線を画するものとなっている。
     本論文に動機づけされた後続研究が数多くなされ、超伝導転移温度も予想通り40Kを越える高いものが報告された。このように本論文は、鉄系超伝導の研究分野に大きな貢献をし、それは100を超える引用数にも表れている。以上のことから、本論文は日本の鉄系高温超伝導研究の高いレベルを示す好例となっており、第26回論文賞に相応しいものである。

  2. The 22nd Outstanding Paper Award of the Physical Society of Japan

    2017.3   The Physical Society of Japan   Charge Ordering in α-(BEDT-TTF)2I3 by Synchrotron X-ray Diffraction

    Toru Kakiuchi, Yusuke Wakabayashi, Hiroshi Sawa, Toshihiro Takahashi, and Toshikazu Nakamura

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    Award type:Award from Japanese society, conference, symposium, etc.  Country:Japan

  3. The 22nd Outstanding Paper Award of the Physical Society of Japan

    2017.3   Charge Ordering in α-(BEDT-TTF)2I3 by Synchrotron X-ray Diffraction

    Toru Kakiuchi, Yusuke Wakabayashi, Hiroshi Sawa, Toshihiro Takahashi, Toshikazu Nakamura

 

Papers 109

  1. Orbital hybridization of donor and acceptor to enhance the conductivity of mixed-stack complexes. International journal

    Tomoko Fujino, Ryohei Kameyama, Kota Onozuka, Kazuki Matsuo, Shun Dekura, Tatsuya Miyamoto, Zijing Guo, Hiroshi Okamoto, Toshikazu Nakamura, Kazuyoshi Yoshimi, Shunsuke Kitou, Taka-Hisa Arima, Hiroyasu Sato, Kaoru Yamamoto, Akira Takahashi, Hiroshi Sawa, Yuiga Nakamura, Hatsumi Mori

    Nature communications   Vol. 15 ( 1 ) page: 3028 - 3028   2024.4

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

    Mixed-stack complexes which comprise columns of alternating donors and acceptors are organic conductors with typically poor electrical conductivity because they are either in a neutral or highly ionic state. This indicates that conductive carriers are insufficient or are mainly localized. In this study, mixed-stack complexes that uniquely exist at the neutral-ionic boundary were synthesized by combining donors (bis(3,4-ethylenedichalcogenothiophene)) and acceptors (fluorinated tetracyanoquinodimethanes) with similar energy levels and orbital symmetry between the highest occupied molecular orbital of the donor and the lowest unoccupied molecular orbital of the acceptor. Surprisingly, the orbitals were highly hybridized in the single-crystal complexes, enhancing the room-temperature conductivity (10-4-0.1 S cm-1) of mixed-stack complexes. Specifically, the maximum conductivity was the highest reported for single-crystal mixed-stack complexes under ambient pressures. The unique electronic structures at the neutral-ionic boundary exhibited structural perturbations between their electron-itinerant and localized states, causing abrupt temperature-dependent changes in their electrical, optical, dielectric, and magnetic properties.

    DOI: 10.1038/s41467-024-47298-1

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  2. Metastable ordered states induced by low-temperature annealing of δ- Ag2/3 V2 O5

    Kubo T., Kojima K., Katayama N., Runčevski T., Dinnebier R.E., Gibbs A.S., Isobe M., Sawa H.

    Physical Review B   Vol. 109 ( 10 )   2024.3

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    Publisher:Physical Review B  

    In δ-Ag2/3V2O5 with charge degrees of freedom in V, it is known that the charge ordering state and physical properties of V that appear at low temperatures depend strongly on the ordering state of Ag. In this study, we focus on the Ag ions in the interlayer and study the structure using synchrotron radiation powder diffraction depending on temperature. We find that when the sample is slowly cooled from room temperature and ordering occurs at the Ag sites, V4+/V5+ charge ordering of V and subsequent V4+-V4+ structural dimers are produced. Although quenching the sample from room temperature suppresses the ordering of Ag, annealing at around 160 K promotes partial ordering of Ag and allows a metastable phase to be realized. This metastable phase is maintained even when the temperature is lowered again, producing a remarkable change in low-temperature properties. These results indicate that the ordered state of Ag, which is the key to control the charge-ordered state and physical properties, can be controlled by low-temperature annealing. The results of this study may provide a methodology for the realization of metastable states in a wide range of material groups of vanadium compounds, in which competition among various charge-ordered states underlies the physical properties.

    DOI: 10.1103/PhysRevB.109.104115

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  3. Enhancement of Superconductivity and Structural Instability by Sn Substitution in LaO0.5F0.5BiS2

    Kobayashi, S; Hara, T; Noguchi, K; Takeda, T; Kurihara, R; Nomura, A; Demura, S; Yaguchi, H; Sawa, H; Sakata, H

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 93 ( 2 )   2024.2

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    Publisher:Journal of the Physical Society of Japan  

    Layered BiS2-based superconductor La(O,F)BiS2 can exhibit superconductivity via carrier doping, and its superconducting properties can be changed by applying hydrostatic or chemical pressure through elemental substitution. Single-crystal LaO0.5F0.5BiS2 exhibits filamentary superconductivity with Tc of approximately 3 K. We found that the partial substitution of Bi with Sn in LaO0.5F0.5BiS2 induces a structural phase transition from the P4=nmm to P21=m structure. Bulk superconductivity with Tc of approximately 6 K emerged near this structural phase transition. We also observed filamentary superconductivity with Tc of approximately 8 K, which was approximately three times higher than that of the unsubstituted sample. This finding provides a new route for further increasing the superconducting transition temperature of this system.

    DOI: 10.7566/JPSJ.93.024707

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  4. Zigzag chain order of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi mathvariant="normal">LiVSe</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math> developing away from the vanadium trimer phase transition boundary

    K. Kojima, N. Katayama, K. Sugimoto, N. Hirao, Y. Ohta, H. Sawa

    Physical Review B   Vol. 108 ( 9 )   2023.9

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

    DOI: 10.1103/physrevb.108.094107

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    Other Link: http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevB.108.094107/fulltext

  5. Visualization of Formula Presented orbital electrons in a pyrochlore-type oxide

    Kitou S., Kaneko Y., Nakamura Y., Sugimoto K., Nomura Y., Arita R., Tokura Y., Sawa H., Arima T.H.

    Physical Review B   Vol. 108 ( 2 )   2023.7

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    Publisher:Physical Review B  

    A real-space observation of the distribution state of valence electrons, which is responsible for physical properties, is a key methodology to understand the relation between the structure and functions of matter. Here, we observe Mo Formula Presented orbital electrons at subangstrom resolution in a pyrochlore-type oxide Formula Presented based on the core differential Fourier synthesis (CDFS) analysis of high-energy x-ray diffraction data. The Formula Presented orbital state is directly determined from the obtained valence electron density (VED) distribution. We also find a dip in the radial profile corresponding to a node of the Formula Presented wave function. The VED distribution around the Nd site might be ascribed to the hybridization of neighboring O Formula Presented with Nd Formula Presented orbitals as well as the anisotropic Formula Presented electrons, which cannot be reproduced by the simple j-j or Formula Presented coupling pictures. In this paper, we demonstrate the usefulness of the CDFS analysis to investigate the orbital states in crystalline materials.

    DOI: 10.1103/PhysRevB.108.024103

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  6. Observation of local atomic displacements intrinsic to the double zigzag chain structure of 1T-MTe2 (M = V, Nb, Ta)

    Katayama, N; Matsuda, Y; Kojima, K; Hara, T; Kitou, S; Mitsuishi, N; Takahashi, H; Ishiwata, S; Ishizaka, K; Sawa, H

    PHYSICAL REVIEW B   Vol. 107 ( 24 )   2023.6

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    Publisher:Physical Review B  

    We describe the existence of local distortion discovered in the synchrotron x-ray single-crystal structure analysis of layered ditelluride 1T-MTe2 (M=V, Nb, Ta). In 1T-TaTe2, the double zigzag chain structure of Ta is deformed at about 170 K, and heptamer molecules are formed periodically at low temperatures. We found that some of the Ta atoms that compose the double zigzag chain structure appearing at high temperatures are locally displaced, resulting in local dimerization. This tendency weakens when Ta is replaced by V or Nb. Our results indicate that the local distortion persistently survives in these ditellurides, where the electronic degrees of freedom, including orbitals, are weakened. We further discuss the origin of local distortion in these ditellurides, which is different from many usual material systems where molecular formation occurs at low temperatures.

    DOI: 10.1103/PhysRevB.107.245113

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  7. Temporal Evolution and Fluence Dependence of Band Structure in Photoexcited Ta<sub>2</sub>Ni<sub>0.9</sub>Co<sub>0.1</sub>Se<sub>5</sub> Probed by Time- and Angle-Resolved Photoemission Spectroscopy

    Yu Takahashi, Takeshi Suzuki, Masaki Hattori, Mario Okawa, Hidenori Takagi, Naoyuki Katayama, Hiroshi Sawa, Minoru Nohara, Yigui Zhong, Kecheng Liu, Teruto Kanai, Jiro Itatani, Shik Shin, Kozo Okazaki, Takashi Mizokawa

    Journal of the Physical Society of Japan   Vol. 92 ( 6 )   2023.6

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    Publishing type:Research paper (scientific journal)   Publisher:Physical Society of Japan  

    DOI: 10.7566/JPSJ.92.064706

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  8. Room-temperature plastic deformation modes of cubic ZnS crystals

    Shunsuke Kitou, Yu Oshima, Atsutomo Nakamura, Katsuyuki Matsunaga, Hiroshi Sawa

    Acta Materialia   Vol. 247   page: 118738 - 118738   2023.4

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

    DOI: 10.1016/j.actamat.2023.118738

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  9. Quasi One-Dimensional Band Structure of Photoinduced Semimetal Phase of Ta<sub>2</sub>Ni<sub>1−</sub><i><sub>x</sub></i>Co<i><sub>x</sub></i>Se<sub>5</sub> (<i>x</i> = 0.0 and 0.1)

    Takumi Mitsuoka, Yu Takahashi, Takeshi Suzuki, Mario Okawa, Hidenori Takagi, Naoyuki Katayama, Hiroshi Sawa, Minoru Nohara, Mari Watanabe, Jiadi Xu, Qianhui Ren, Masami Fujisawa, Teruto Kanai, Jiro Itatani, Kozo Okazaki, Shik Shin, Takashi Mizokawa

    Journal of the Physical Society of Japan   Vol. 92 ( 2 )   2023.2

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    Publishing type:Research paper (scientific journal)   Publisher:Physical Society of Japan  

    DOI: 10.7566/JPSJ.92.023703

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  10. Pressure suppression of the excitonic insulator state in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>Ta</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mi>NiSe</mml:mi><mml:mn>5</mml:mn></mml:msub></mml:mrow></mml:math> observed by optical conductivity

    H. Okamura, T. Mizokawa, K. Miki, Y. Matsui, N. Noguchi, N. Katayama, H. Sawa, M. Nohara, Y. Lu, H. Takagi, Y. Ikemoto, T. Moriwaki

    Physical Review B   Vol. 107 ( 4 )   2023.1

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

    DOI: 10.1103/PhysRevB.107.045141

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    Other Link: http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevB.107.045141/fulltext

  11. Short-range order and increased transition temperature in LiVO2 with weakened trimer frustration

    Kojima, K; Kattayama, N; Matsuda, Y; Shiomi, M; Ishii, R; Sawa, H

    PHYSICAL REVIEW B   Vol. 107 ( 2 )   2023.1

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    Publisher:Physical Review B  

    Vanadium atoms in layered LiVO2 form in-plane periodic vanadium trimers at low temperatures, but the trimers appear randomly in the stacking direction because there are many trimer configurations with comparable lattice energy. We detailed an original modeling scheme to represent glassy states with a completely disordered trimer configuration in the stacking structure. Through pair distribution function analysis using this model, we show that the synthesis method can yield two types of low-temperature stacking structures: a completely disordered stacking structure and a short-range order in the stacking structure. The phase-transition temperature of the former sample is about 15 K lower than that of the latter. We discuss that this is due to the strong trimer frustration that appears in the sample without short-range order, which suppresses the phase-transition temperature, similar to the frustration effect in conventional spin systems.

    DOI: 10.1103/PhysRevB.107.L020101

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  12. Spin-orbital liquid state and liquid-gas metamagnetic transition on a pyrochlore lattice

    Tang, N; Gritsenko, Y; Kimura, K; Bhattacharjee, S; Sakai, A; Fu, MX; Takeda, H; Man, HY; Sugawara, K; Matsumoto, Y; Shimura, Y; Wen, JJ; Broholm, C; Sawa, H; Takigawa, M; Sakakibara, T; Zherlitsyn, S; Wosnitza, J; Moessner, R; Nakatsuji, S

    NATURE PHYSICS   Vol. 19 ( 1 ) page: 92 - +   2023.1

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    Publisher:Nature Physics  

    Crystal structures with degenerate electronic orbitals are unstable towards lattice distortions that lift the degeneracy. Although these Jahn–Teller distortions have profound effects on magnetism, they are typically unaffected by the onset of magnetic ordering because of a separation in energy scales. Here we show the contrary case in Pr2Zr2O7, where orbital degeneracy remains down to the millikelvin range due to an interplay between spins and orbitals. Pr2Zr2O7 is a multipolar spin ice with strongly localized 4f electrons in an even-number configuration, giving rise to a non-Kramers doublet that carries transverse quadrupolar and longitudinal dipolar moments. Our study of ultrapure single crystals of Pr2Zr2O7 finds comprehensive evidence for enhanced spin–orbital quantum dynamics of the non-Kramers doublet. This dynamical Jahn–Teller effect is encapsulated by the liquid–gas metamagnetic transition that is characteristic of spin ice being accompanied by strong lattice softening. This behaviour suggests that a spin–orbital liquid state forms on the pyrochlore lattice at low temperatures and low magnetic fields.

    DOI: 10.1038/s41567-022-01816-4

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  13. Do electron distributions with orbital degree of freedom exhibit anisotropy? Reviewed

    Taishun Manjo, Shunsuke Kitou, Naoyuki Katayama, Shin Nakamura, Takuro Katsufuji, Yoichi Nii, Taka-hisa Arima, Joji Nasu, Takumi Hasegawa, Kunihisa Sugimoto, Daisuke Ishikawa, Alfred Q. R. Baron, Hiroshi Sawa

    MATERIALS ADVANCES   Vol. 3 ( 7 ) page: 3192 - 3198   2022.4

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:ROYAL SOC CHEMISTRY  

    Orbital degrees of freedom appear in partially filled degenerate orbitals and are responsible for a variety of physical properties. Although many methods for directly observing orbital states in ordered states have been proposed, it is difficult to determine degenerate orbital states directly. We found that high-precision diffraction data obtained by synchrotron radiation X-rays can be used to observe only the valence electron density distribution with minimal analytical bias. The results obtained using this method clearly showed the anisotropy of the partially filled degenerate 3d orbital states in spinel vanadium oxide FeV2O4. The 3d orbital quantum state was successfully determined from this anisotropy.

    DOI: 10.1039/d1ma01113h

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  14. Charge and Lattice Dynamics in Excitonic Insulator Ta<sub>2</sub>NiSe<sub>5</sub> Investigated Using Ultrafast Reflection Spectroscopy Reviewed

    Miyamoto, T; Mizui, M; Takamura, N; Hirata, J; Yamakawa, H; Morimoto, T; Terashige, T; Kida, N; Nakano, A; Sawa, H; Okamoto, H

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 91 ( 2 )   2022.2

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    Language:Japanese   Publisher:Journal of the Physical Society of Japan  

    An excitonic insulator, in which an optical gap is formed by exciton condensation, is expected to exhibit large photoresponses. Here, we report the results of femtosecond reflection spectroscopy covering a wide infrared region on a typical excitonic insulator, Ta2NiSe5, which gives direct information not only about a change of excitonic gap but also a metallization. With a weak excitation, the excitonic gap decreases due to the weakening of excitonic effect by photocarriers. With a strong excitation, a Drude-like high-reflection band appears, showing an excitonic-insulator-to-metal transition. Analyses of spectral and temporal changes of reflectivity revealed that the metallization is accompanied by large structural changes. This demonstrates an important role of electron–lattice interaction on the stabilization of excitonic phase.

    DOI: 10.7566/JPSJ.91.023701

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  15. Charge-ordered state satisfying the Anderson condition in LiRh2O4 arising from local dimer order

    M. Shiomi, K. Kojima, N. Katayama, S. Maeda, J. A. Schneeloch, S. Yamamoto, K. Sugimoto, Y. Ohta, D. Louca, Y. Okamoto, H. Sawa

    Physical Review B   Vol. 105 ( 4 )   2022.1

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

    DOI: 10.1103/PhysRevB.105.L041103

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    Other Link: http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevB.105.L041103/fulltext

  16. Hybridization-Gap Formation and Superconductivity in the Pressure-Induced Semimetallic Phase of the Excitonic Insulator Ta2NiSe5

    Kazuyuki Matsubayashi, Hidekazu Okamura, Takashi Mizokawa, Naoyuki Katayama, Akitoshi Nakano, Hiroshi Sawa, Tatsuya Kaneko, Tatsuya Toriyama, Takehisa Konishi, Yukinori Ohta, Hiroto Arima, Rina Yamanaka, Akihiko Hisada, Taku Okada, Yuka Ikemoto, Taro Moriwaki, Koji Munakata, Akiko Nakao, Minoru Nohara, Yangfan Lu, Hidenori Takagi, Yoshiya Uwatoko

    Journal of the Physical Society of Japan   Vol. 90 ( 7 ) page: 074706 - 074706   2021.7

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:Physical Society of Japan  

    DOI: 10.7566/JPSJ.90.074706

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  17. Complex changes in structural parameters hidden in the universal phase diagram of the quasi-one-dimensional organic conductors (TMTTF)2X ( X=NbF6, AsF6, PF6 , and Br) Reviewed

    Shunsuke Kitou, Lidong Zhang, Toshikazu Nakamura, Hiroshi Sawa

    Physical Review B   Vol. 103 ( 18 )   2021.5

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

    DOI: 10.1103/PhysRevB.103.184112

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  18. Tetramethyltetrathiafulvalene [(NbOF4)−]∞: One-Dimensional Charge Transfer Salt with an Infinite Anion Chain

    Toshikazu Nakamura, Lidong Zhang, Shunsuke Kitou, Hiroshi Sawa

    Inorganic Chemistry   Vol. 60 ( 7 ) page: 5206 - 5211   2021.4

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:American Chemical Society (ACS)  

    DOI: 10.1021/acs.inorgchem.1c00208

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  19. Detecting electron-phonon coupling during photoinduced phase transition

    Takeshi Suzuki, Yasushi Shinohara, Yangfan Lu, Mari Watanabe, Jiadi Xu, Kenichi L. Ishikawa, Hide Takagi, Minoru Nohara, Naoyuki Katayama, Hiroshi Sawa, Masami Fujisawa, Teruto Kanai, Jiro Itatani, Takashi Mizokawa, Shik Shin, Kozo Okazaki

    PHYSICAL REVIEW B   Vol. 103 ( 12 )   2021.3

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

    Photoinduced phase transitions have been intensively studied owing to the potential capability to control a material of interest in the ultrafast manner, which can induce exotic phases unable to be attained at equilibrium. However, the key mechanisms are still under debate, and it is currently a central issue as to how the couplings between the electron, lattice, and spin degrees of freedom are evolving during photoinduced phase transitions. Here, we use a recently developed analysis method, which we call frequency-domain angle-resolved photoemission spectroscopy (FDARPES), and reveal mode- and band-selective electron-phonon couplings during the photoinduced insulator-to-metal transition for Ta2NiSe5. We find that the lattice modulation corresponding to the 2 THz phonon mode, where the Ta lattice is sheared along the a axis, is the most relevant for the emergence of photoinduced semimetallic state. Furthermore, we find that the semimetallic and semiconducting bands coexist in the transient state, and demonstrate that FDARPES spectra can selectively detect the phonon-specific couplings to the two coexistent band structures during the photoinduced phase transition by resolving them in the frequency domain.

    DOI: 10.1103/PhysRevB.103.L121105

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  20. Slow dynamics of disordered zigzag chain molecules in layered LiVS2 under electron irradiation

    Naoyuki Katayama, Keita Kojima, Tomoki Yamaguchi, Sosuke Hattori, Shinya Tamura, Koji Ohara, Shintaro Kobayashi, Koudai Sugimoto, Yukinori Ohta, Koh Saitoh, Hiroshi Sawa

    npj Quantum Materials   Vol. 6 ( 1 )   2021.2

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    Publishing type:Research paper (scientific journal)   Publisher:Springer Science and Business Media LLC  

    <title>Abstract</title>Electronic instabilities in transition metal compounds often spontaneously form orbital molecules, which consist of orbital-coupled metal ions at low temperature. Recent local structural studies utilizing the pair distribution function revealed that preformed orbital molecules appear disordered even in the high-temperature paramagnetic phase. However, it is unclear whether preformed orbital molecules are dynamic or static. Here, we provide clear experimental evidence of the slow dynamics of disordered orbital molecules realized in the high-temperature paramagnetic phase of LiVS<sub>2</sub>, which exhibits vanadium trimerization upon cooling below 314 K. Unexpectedly, the preformed orbital molecules appear as a disordered zigzag chain that fluctuate in both time and space under electron irradiation. Our findings should advance studies on soft matter physics realized in an inorganic material due to disordered orbital molecules.

    DOI: 10.1038/s41535-021-00313-w

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    Other Link: http://www.nature.com/articles/s41535-021-00313-w

  21. Ambient-pressure Dirac electron system in the quasi-two-dimensional molecular conductor α−(BETS)2I3 Reviewed

    Shunsuke Kitou, Takao Tsumuraya, Hikaru Sawahata, Fumiyuki Ishii, Ko-ichi Hiraki, Toshikazu Nakamura, Naoyuki Katayama, Hiroshi Sawa

    Physical Review B   Vol. 103 ( 3 )   2021.1

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    We investigated the precise crystal structures and electronic states in a
    quasi-two-dimensional molecular conductor ${\alpha}$-(BETS)$_2$I$_3$ at ambient
    pressure. The electronic resistivity of this molecular solid shows a
    metal-to-insulator (MI) crossover at $T_{MI}$=50 K. Our x-ray diffraction and
    $^{13}$C nuclear magnetic resonance experiments revealed that
    ${\alpha}$-(BETS)$_2$I$_3$ maintains the inversion symmetry below $T_{MI}$. The
    first-principles calculations found a pair of anisotropic Dirac cones at a
    general k-point, where the degenerated contact points are located at the Fermi
    level. Furthermore, the origin of the insulating state in this system is
    explained by a small energy gap of ~2 meV opened by a spin-orbit interaction,
    in which the Z$_2$ topological invariants indicate a weak topological
    insulator. Our results suggest that ${\alpha}$-(BETS)$_2$I$_3$ is a promising
    material for studying the bulk Dirac electron system in two-dimension.

    DOI: 10.1103/PhysRevB.103.035135

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    Other Link: http://arxiv.org/pdf/2006.08978v1

  22. Successive Structural Transitions of CrSe<sub>2</sub> with Anomalous Valent Chromium

    Shintaro KOBAYASHI, Naoyuki KATAYAMA, Hiroshi SAWA

    Nihon Kessho Gakkaishi   Vol. 62 ( 4 ) page: 221 - 222   2020.12

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    DOI: 10.5940/jcrsj.62.221

  23. Photoinduced Phase Transition from Excitonic Insulator to Semimetal-like State in Ta2Ni1−xCoxSe5 (x = 0.10)

    Takumi Mitsuoka, Takeshi Suzuki, Hidenori Takagi, Naoyuki Katayama, Hiroshi Sawa, Minoru Nohara, Mari Watanabe, Jiadi Xu, Qianhui Ren, Masami Fujisawa, Teruto Kanai, Jiro Itatani, Shik Shin, Kozo Okazaki, Takashi Mizokawa

    Journal of the Physical Society of Japan   Vol. 89 ( 12 ) page: 124703 - 124703   2020.12

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    DOI: 10.7566/JPSJ.89.124703

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  24. Direct Observation of Molecular Orbitals Using Synchrotron X-ray Diffraction Reviewed

    Shunsuke Kitou, Yuto Hosogi, Ryo Kitaura, Toshio Naito, Toshikazu Nakamura, Hiroshi Sawa

    Crystals   Vol. 10 ( 11 ) page: 998 - 998   2020.11

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    The physical properties of molecular crystals are governed by the frontier orbitals of molecules. A molecular orbital, which is formed by superposing the atomic orbitals of constituent elements, has complicated degrees of freedom in the crystal because of the influence of electron correlation and crystal field. Therefore, in general, it is difficult to experimentally observe the whole picture of a frontier orbital. Here, we introduce a new method called “core differential Fourier synthesis” (CDFS) using synchrotron X-ray diffraction to observe the valence electron density in materials. By observing the valence electrons occupied in molecular orbitals, the orbital state can be directly determined in a real space. In this study, we applied the CDFS method to molecular materials such as diamond, C60 fullerene, (MV)I2, and (TMTTF)2X. Our results not only demonstrate the typical orbital states in some materials, but also provide a new method for studying intramolecular degrees of freedom.

    DOI: 10.3390/cryst10110998

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  25. Collapse of the simple localized 3d(1) orbital picture in Mott insulator Reviewed

    Shunsuke Kitou, Taishun Manjo, Naoyuki Katayama, Tatsuya Shishidou, Taka-hisa Arima, Yasujiro Taguchi, Yoshinori Tokura, Toshikazu Nakamura, Toshihiko Yokoyama, Kunihisa Sugimoto, Hiroshi Sawa

    PHYSICAL REVIEW RESEARCH   Vol. 2 ( 3 )   2020.9

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    The orbital degree of freedom of electrons greatly influences the physical properties of materials such as magnetic order and unconventional superconductivity. An orbital is a minimal unit of "shape," and the orbital state can be unraveled by observing the spatial anisotropic distribution of electrons. However, it is difficult to experimentally extract the orbital information in a crystal because of various technical problems. Here, the Ti-3d orbital state in perovskite-type oxides RTiO3 (R = Y, Sm, and La) is directly determined by a core differential Fourier synthesis (CDFS) method using synchrotron x-ray diffraction. The valence electron-density distribution, including information on the anisotropy and the hybridization between atomic orbitals, can be extracted from the CDFS analysis. Our study not only demonstrates the relationship between the magnetic- and orbital-ordered states called the Kugel-Khomskii model, but also provides a nontrivial picture of the orbital state reconstructed by the orbital hybridization.

    DOI: 10.1103/PhysRevResearch.2.033503

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  26. Robust atomic orbital in the cluster magnet LiMoO2

    N. Katayama, H. Takeda, T. Yamaguchi, Y. Yamada, K. Iida, M. Takigawa, Y. Ohta, H. Sawa

    Physical Review B   Vol. 102 ( 8 )   2020.8

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    DOI: 10.1103/PhysRevB.102.081106

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    Other Link: http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevB.102.081106/fulltext

  27. Regular-triangle trimer and charge order preserving the Anderson condition in the pyrochlore structure of CsW2O6

    Yoshihiko Okamoto, Haruki Amano, Naoyuki Katayama, Hiroshi Sawa, Kenta Niki, Rikuto Mitoka, Hisatomo Harima, Takumi Hasegawa, Norio Ogita, Yu Tanaka, Masashi Takigawa, Yasunori Yokoyama, Kanji Takehana, Yasutaka Imanaka, Yuto Nakamura, Hideo Kishida, Koshi Takenaka

    NATURE COMMUNICATIONS   Vol. 11 ( 1 )   2020.6

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    Since the discovery of the Verwey transition in magnetite, transition metal compounds with pyrochlore structures have been intensively studied as a platform for realizing remarkable electronic phase transitions. We report on a phase transition that preserves the cubic symmetry of the beta -pyrochlore oxide CsW2O6, where each of W 5d electrons are confined in regular-triangle W-3 trimers. This trimer formation represents the self-organization of 5d electrons, which can be resolved into a charge order satisfying the Anderson condition in a nontrivial way, orbital order caused by the distortion of WO6 octahedra, and the formation of a spin-singlet pair in a regular-triangle trimer. An electronic instability due to the unusual three-dimensional nesting of Fermi surfaces and the strong correlations of the 5d electrons characteristic of the pyrochlore oxides are both likely to play important roles in this charge-orbital-spin coupled phenomenon. Many rules have been suggested to rationalize the behaviour of transition metal oxides but the complex underlying physics often leads to deviations from the expected behaviour. Here the authors show that the metal-insulator transition in CsW2O6 satisfies the Anderson condition in an unusual way.

    DOI: 10.1038/s41467-020-16873-7

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  28. Intercalated Cu+ ion dynamics in the two-dimensional layered compound Cu0.33TiSe2

    Shunsuke Kitou, Takumi Hasegawa, Akitoshi Nakano, Naoyuki Katayama, Satoshi Tsutsui, Hiroshi Sawa

    PHYSICAL REVIEW B   Vol. 101 ( 9 )   2020.3

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    Cu+ ion behavior is one of the heavily discussed topics in physical and material fields because of its unclear behavior and high potential in materials application. To provide a breakthrough in this field, comprehensive research that connects the real space and the reciprocal lattice (momentum) space is effective. Here, we investigated the Cu+ ion behavior in two-dimensional layered system Cu0.33TiSe2, which shows the Cu+ disorder-order phase transition at 200 K. Inelastic x-ray scattering revealed a large change of the Cu+ ion dynamics at the phase transition. It is expected that the complex interactions are involved in the behavior of Cu+ ions intercalated in the negatively charged TiSe2 layers by charge transfer. However, Monte Carlo simulations using a simple combination of repulsive forces between Cu+ ions well reproduce the characteristic temperature dependence of the anisotropic diffuse scattering. These insights provide a unified understanding in controlling the intercalated system.

    DOI: 10.1103/PhysRevB.101.094108

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  29. Resistive anisotropy of candidate excitonic insulator Ta2NiSe5 under pressure

    Arima H., Naito Y., Kudo K., Katayama N., Sawa H., Nohara M., Lu Y. F., Kitagawa K., Takagi H., Uwatoko Y., Matsubayashi K.

    27TH AIRAPT INTERNATIONAL CONFERENCE ON HIGH PRESSURE SCIENCE AND TECHNOLOGY   Vol. 1609   2020

  30. Valence-bond insulator in proximity to excitonic instability Reviewed

    Y. Chiba, T. Mitsuoka, N. L. Saini, K. Horiba, M. Kobayashi, K. Ono, H. Kumigashira, N. Katayama, H. Sawa, M. Nohara, Y. F. Lu, H. Takagi, T. Mizokawa

    Physical Review B   Vol. 100 ( 24 )   2019.12

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    © 2019 American Physical Society. Ta2NiS5 is supposed to be a simple semiconductor in which excitonic instability of Ta2NiSe5 is suppressed due to its large band gap. However, the Ni 2p core-level photoemission of Ta2NiS5 exhibits a satellite indicating Ni 3d orbitals are mixed into its conduction band as expected in an excitonic insulator. The valence band does not show dispersion flattening and spectral sharpening which are fingerprints of an excitonic insulator. Instead, Ni 3p-3d resonant photoemission indicates Mottness of the Ni 3d electron in Ta2NiS5 with negative charge-transfer energy. The present results show that Ta2NiS5 can be viewed as a valence bond insulator with a band gap exceeding the exciton binding energy.

    DOI: 10.1103/PhysRevB.100.245129

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  31. Vanadium trimers randomly aligned along the c-axis direction in layered LiVO2 Reviewed

    Kojima K, Katayama N, Tamura S, Shiomi M, Sawa H

    PHYSICAL REVIEW B   Vol. 100 ( 23 )   2019.12

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    DOI: 10.1103/PhysRevB.100.235120

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  32. Thermal Conductivity of the Quantum Spin Liquid Candidate EtMe3Sb [Pd (dmit)2] 2: No Evidence of Mobile Gapless Excitations

    Bourgeois-Hope P., Laliberté F., Lefrançois E., Grissonnanche G., De Cotret S.R., Gordon R., Kitou S., Sawa H., Cui H., Kato R., Taillefer L., Doiron-Leyraud N.

    Physical Review X   Vol. 91 ( 4 )   2019.12

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    The thermal conductivity κ of the quasi-2D organic spin-liquid candidate EtMe3Sb[Pd(dmit)2]2 (dmit-131) was measured at low temperatures, down to 0.07 K. We observe a vanishingly small residual linear term κ0/T, in κ/T vs T as T→0. This shows that the low-energy excitations responsible for the sizable residual linear term γ in the specific heat C, seen in C/T vs T as T→0, are localized. We conclude that there are no mobile gapless excitations in this spin-liquid candidate, in contrast with a prior study of dmit-131 that reported a large κ0/T value [Yamashita, Science 328, 1246 (2010)SCIEAS0036-807510.1126/science.1188200]. Our study shows that dmit-131 is in fact similar to κ-(BEDT-TTF)2Cu2(CN)3, another quasi-2D organic spin-liquid candidate where a vanishingly small κ0/T and a sizable γ are seen. We attribute heat conduction in these organic insulators without magnetic order to phonons undergoing strong spin-phonon scattering, as observed in several other spin-liquid materials.

    DOI: 10.1103/PhysRevX.9.041051

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  33. Exciton transport in the electron–hole system Ta<inf>2</inf>NiSe<inf>5</inf> Reviewed

    Akitoshi Nakano, Takayuki Nagai, Naoyuki Katayama, Hiroshi Sawa, Hiroki Taniguchi, Ichiro Terasaki

    Journal of the Physical Society of Japan   Vol. 88 ( 11 )   2019.11

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    ©2019 The Physical Society of Japan We have measured the dielectric constant and thermopower of single crystal samples of the excitonic insulator candidate Ta2NiSe5. The dielectric constant below 50 K shows relaxor-like relaxation, implying the existence of randomly distributed electric dipoles. We have evaluated the concentration of the dipoles to be 1019 cm−3 at 30 K, which gives a rough estimate of the exciton concentration in this compound. A large thermopower of 600 µV=K at 100 K suddenly drops toward zero down to 50 K, and this zero thermopower evidences the neutral particles flow against the applied temperature gradient. We have semi-quantitatively explained the above two anomalies in terms of spontaneously generated excitons at low temperatures where thermally excited holes are quenched.

    DOI: 10.7566/JPSJ.88.113706

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  34. Linear Trimer Formation with Antiferromagnetic Ordering in 1T-CrSe2 Originating from Peierls-like Instabilities and Interlayer Se–Se Interactions Reviewed

    S. Kobayashi, N. Katayama, T. Manjo, H. Ueda, C. Michioka, J. Sugiyama, Y. Sassa, O. K. Forslund, M. Månsson, K. Yoshimura, H. Sawa

    Inorg. Chem.   Vol. 58 ( 21 ) page: 14304 - 14315   2019.11

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    DOI: 10.1021/acs.inorgchem.9b00186

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  35. Two magnetization plateaus in the kagome fluoride Cs2LiTi3F12 Reviewed

    Ryu Shirakami, Hiroaki Ueda, Harald O. Jeschke, Hiroki Nakano, Shintaro Kobayashi, Akira Matsuo, Tôru Sakai, Naoyuki Katayama, Hiroshi Sawa, Koichi Kindo, Chishiro Michioka, Kazuyoshi Yoshimura

    Physical Review B   Vol. 100 ( 17 ) page: 174401   2019.11

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    DOI: 10.1103/PhysRevB.100.174401

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  36. A molecular crystal with an unprecedentedly long-lived photoexcited state Reviewed

    Toshio Naito, Naoki Watanabe, Yuuka Sakamoto, Yuuko Miyaji, Takashi Shirahata, Yohji Misaki, Shunsuke Kitou, Hiroshi Sawa

    Dalton Transactions   Vol. 48 ( 34 ) page: 12858 - 12866   2019.9

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    <p>Gold(<sc>iii</sc>) atoms reversibly deviate from the molecular plane on receiving thermal and photon energy.</p>

    DOI: 10.1039/c9dt02377a

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  37. Weak Ferroelectricity in n = 2 Pseudo Ruddlesden-Popper-Type Niobate Li<inf>2</inf>SrNb<inf>2</inf>O<inf>7</inf> Reviewed

    Takayuki Nagai, Hirokazu Shirakuni, Akitoshi Nakano, Hiroshi Sawa, Hiroki Moriwake, Ichiro Terasaki, Hiroki Taniguchi

    Chemistry of Materials   Vol. 31 ( 16 ) page: 6257 - 6261   2019.8

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    © 2019 American Chemical Society. Li2SrNb2O7 (LSNO) crystallizes in a structure closely related to n = 2 Ruddlesden-Popper-type compounds, which are generally formed by intergrowth of two-dimensional perovskite-type blocks and rocksalt-type layers. The present study demonstrates the coexistence of spontaneous polarization and an anti-ferroelectric-like nonlinear response in LSNO at 80 K, suggesting weak ferroelectricity below the phase transition temperature of 217 K. A combination of first-principles calculations and single-crystal X-ray diffractions clarifies a polar P21cn structure for the ground state of LSNO, where an in-plane antiferroelectric displacement and an out-of-plane polar shift simultaneously take place. The present study offers a new perspective to design ferroelectric and antiferroelectric materials with Ruddlesden-Popper-type compounds.

    DOI: 10.1021/acs.chemmater.9b02373

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  38. Effect of Cu intercalation and pressure on excitonic interaction in 1T-TiSe2

    Kitou S, Nakano A, Kobayashi S, Sugawara K, Katayama N, Maejima N, Machida A, Watanuki T, Ichimura K, Tanda S, Nakamura T, Sawa H

    PHYSICAL REVIEW B   Vol. 99 ( 10 )   2019.3

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    DOI: 10.1103/PhysRevB.99.104109

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  39. Ganglioside Synthase Knockout Reduces Prion Disease Incubation Time in Mouse Models

    Kobayashi A., Qi Z., Shimazaki T., Munesue Y., Miyamoto T., Isoda N., Sawa H., Aoshima K., Kimura T., Mohri S., Kitamoto T., Yamashita T., Miyoshi I.

    American Journal of Pathology   Vol. 189 ( 3 ) page: 677 - 686   2019.3

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    Localization of the abnormal and normal isoforms of prion proteins to detergent-resistant membrane microdomains, lipid rafts, is important for the conformational conversion. Lipid rafts are enriched in sialic acid–containing glycosphingolipids (namely, gangliosides). Alteration in the ganglioside composition of lipid rafts can affect the localization of lipid raft–associated proteins. To investigate the role of gangliosides in the pathogenesis of prion diseases, we performed intracerebral transmission study of a scrapie prion strain Chandler and a Gerstmann-Sträussler-Scheinker syndrome prion strain Fukuoka-1 using various knockout mouse strains ablated with ganglioside synthase gene (ie, GD2/GM2 synthase, GD3 synthase, or GM3 synthase). After challenge with the Chandler strain, GD2/GM2 synthase knockout mice showed 20% reduction of incubation time, reduced prion protein deposition in the brain with attenuated glial reactions, and reduced localization of prion proteins to lipid rafts. These results raise the possibility that the gangliosides may have an important role in prion disease pathogenesis by affecting the localization of prion proteins to lipid rafts.

    DOI: 10.1016/j.ajpath.2018.11.009

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  40. Honeycomb lattice type charge density wave associated with interlayer Cu ions ordering in 1T-CuxTiSe2

    Kitou Shunsuke, Kobayashi Shintaro, Kaneko Tatsuya, Katayama Naoyuki, Yunoki Seiji, Nakamura Toshikazu, Sawa Hiroshi

    PHYSICAL REVIEW B   Vol. 99 ( 8 )   2019.2

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    The phase transition phenomenon in a semimetallic 1T-TiSe2 has attracted attention as an excitonic insulator. However, as the phase transition accompanying superlattice peaks has the q vector connecting the Fermi surfaces of the three-dimensional shape of hole and electron pockets, it also assumes the charge density wave (CDW) state owing to the electron-phonon interaction. To understand the electronic state at the low temperature, control of the chemical potential was attempted by electronic doping through Cu+ intercalation. Physical properties measurements and synchrotron x-ray diffraction experiments in CuxTiSe2 (x=0-0.35) were performed. The phase transition was determined to occur as a cooperative phenomenon between the honeycomb lattice type CDW corresponding to the nesting vector and the ordered state of the Cu+ ions between TiSe2 layers at a specific doping amount (x=1/3). The behavior of Cu+ ions in highly doped regions suggests the occurrence of a two-dimensional liquid-solid state transition based on the temperature dependence of the x-ray diffuse scattering.

    DOI: 10.1103/PhysRevB.99.081111

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  41. Spin-orbital entangled liquid state in the copper oxide Ba3CuSb2O9 Reviewed

    Man Huiyuan, Halim Mario, Sawa Hiroshi, Hagiwara Masayuki, Wakabayashi Yusuke, Nakatsuji Satoru

    JOURNAL OF PHYSICS-CONDENSED MATTER   Vol. 30 ( 44 )   2018.11

  42. Photo-induced semimetallic states realised in electron-hole coupled insulators Reviewed International journal

    Okazaki Kozo, Ogawa Yu, Suzuki Takeshi, Yamamoto Takashi, Someya Takashi, Michimae Shoya, Watanabe Mari, Lu Yangfan, Nohara Minoru, Takagi Hidenori, Katayama Naoyuki, Sawa Hiroshi, Fujisawa Masami, Kanai Teruto, Ishii Nobuhisa, Itatani Jiro, Mizokawa Takashi, Shin Shik

    NATURE COMMUNICATIONS   Vol. 9 ( 1 ) page: 4322 - 4322   2018.10

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    Using light to manipulate materials into desired states is one of the goals in condensed matter physics, since light control can provide ultrafast and environmentally friendly photonics devices. However, it is generally difficult to realise a photo-induced phase which is not merely a higher entropy phase corresponding to a high-temperature phase at equilibrium. Here, we report realisation of photo-induced insulator-to-metal transitions in Ta2Ni(Se1-xSx)5 including the excitonic insulator phase using time- and angle-resolved photoemission spectroscopy. From the dynamic properties of the system, we determine that screening of excitonic correlations plays a key role in the timescale of the transition to the metallic phase, which supports the existence of an excitonic insulator phase at equilibrium. The non-equilibrium metallic state observed unexpectedly in the direct-gap excitonic insulator opens up a new avenue to optical band engineering in electron-hole coupled systems.

    DOI: 10.1038/s41467-018-06801-1

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  43. Improved color uniformity in white light-emitting diodes using newly developed phosphors Reviewed

    Daicho Hisayoshi, Enomoto Kiminori, Sawa Hiroshi, Matsuishi Satoru, Hosono Hideo

    OPTICS EXPRESS   Vol. 26 ( 19 ) page: 24784 - 24791   2018.9

  44. Large entropy change derived from orbitally assisted three-centered two-electron σ bond formation in metallic Li0.33VS2

    N. Katayama, S. Tamura, T. Yamaguchi, K. Sugimoto, K. Iida, T. Matsukawa, A. Hoshikawa, T. Ishigaki, S. Kobayashi, Y. Ohta, H. Sawa

    Physical Review B   Vol. 98 ( 8 )   2018.8

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    © 2018 American Physical Society. We discuss herein the emergence of a large entropy change in metallic Li0.33VS2 derived from orbitally assisted loose σ bond formation. Comprehensive structural studies based on synchrotron x-ray and neutron diffraction analyses clarify the fabrication of ribbon chains at 375 K, consisting of multiple three-centered two-electron σ bonds based on the viewpoint of local chemical bonding. Although the metallic conductivity persists down to the lowest temperature measured, an exceptionally large entropy change as a metal, as much as ΔS=6.6Jmol-1K-1, appears at the transition. The emergence of a large entropy change in a metallic state may possibly lead to different functional materials, such as a heat-storage material with a rapid thermal response.

    DOI: 10.1103/PhysRevB.98.081104

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  45. Antiferroelectric distortion with anomalous phonon softening in the excitonic insulator Ta2NiSe5

    Akitoshi Nakano, Takumi Hasegawa, Shinya Tamura, Naoyuki Katayama, Satoshi Tsutsui, Hiroshi Sawa

    Physical Review B   Vol. 98 ( 4 )   2018.7

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    © 2018 American Physical Society. Ta2NiSe5 is considered a promising excitonic insulator (EI) candidate, in which the EI state is due to Coulomb interaction between electrons and holes. In Ta2NiSe5, the role of phonons is significant since the EI transition is accompanied by an orthorhombic-to-monoclinic structural transition at Ts=328K. Our inelastic x-ray scattering measurements reveal that the transverse acoustic mode exhibits strong softening just above Ts. Furthermore, the transverse optical mode exhibits linewidth broadening caused by strong electron-optical-phonon coupling above Ts. Density functional theory calculations indicate that the coupled optical modes arise due to the vibration of Ta ions. Consequently, in the monoclinic phase, the coupled optical modes are &quot;frozen&quot; such that Ta and Se approach each other, forming atomic-displacement-type electric dipoles that are obviously different from a Peierls transition or Jahn-Teller distortion. The characteristic of electronic toroidal moment formation by the antiferroelectric arrangements of the electric dipoles forms the common feature between Ta2NiSe5 and 1T-TiSe2.

    DOI: 10.1103/PhysRevB.98.045139

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  46. In-plane spin canting and 1/3-magnetization-plateaulike behavior in S=3/2 Cr3+ kagome lattice antiferromagnets Cs2KCr3 F12 and Cs2NaCr3 F12

    Masato Goto, Hiroaki Ueda, Chishiro Michioka, Akira Matsuo, Koichi Kindo, Kento Sugawara, Shintaro Kobayashi, Naoyuki Katayama, Hiroshi Sawa, Kazuyoshi Yoshimura

    Physical Review B   Vol. 97 ( 22 )   2018.6

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    We have investigated the structural and magnetic properties of S=3/2Cr3+ Heisenberg-like kagome lattice antiferromagnets Cs2KCr3F12 and Cs2NaCr3F12 using single crystals. Each compound has a slightly distorted kagome lattice, although the space groups differ for the two compounds. The magnetic data suggest that each compound exhibits the formation of antiferromagnetic ordering with in-plane-spin canting approximately below 6 K. The in-plane coplanar structures are clearly different from disordered ground states of the isostructural Ti3+ compounds and out-of-plane coplanar structures of the V3+ compounds, which is mainly caused by the differences in the strength of quantum fluctuation and the strength of magnetic anisotropy for these three spin systems. In contrast, as well as the Ti3+ and V3+ compounds, the magnetization curves show 1/3-magnetization-plateaulike anomalies.

    DOI: 10.1103/PhysRevB.97.224421

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  47. Anomalous double-stripe charge ordering in beta-NaFe2O3 with double triangular layers consisting of almost perfect regular Fe-4 tetrahedra Reviewed

    Kobayashi Shintaro, Ueda Hiroaki, Michioka Chishiro, Yoshimura Kazuyoshi, Nakamura Shin, Katsufuji Takuro, Sawa Hiroshi

    PHYSICAL REVIEW MATERIALS   Vol. 2 ( 5 )   2018.5

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    DOI: 10.1103/PhysRevMaterials.2.054402

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  48. Pressure-induced coherent sliding-layer transition in the excitonic insulator Ta2NiSe5

    Akitoshi Nakano, Kento Sugawara, Shinya Tamura, Naoyuki Katayama, Kazuyuki Matsubayashi, Taku Okada, Yoshiya Uwatoko, Kouji Munakata, Akiko Nakao, Hajime Sagayama, Reiji Kumai, Kunihisa Sugimoto, Naoyuki Maejima, Akihiko Machida, Tetsu Watanuki, Hiroshi Sawa

    IUCrJ   Vol. 5   page: 158 - 165   2018.3

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    The crystal structure of the excitonic insulator Ta2NiSe5 has been investigated under a range of pressures, as determined by the complementary analysis of both single-crystal and powder synchrotron X-ray diffraction measurements. The monoclinic ambient-pressure excitonic insulator phase II transforms upon warming or under a modest pressure to give the semiconducting C-centred orthorhombic phase I. At higher pressures (i.e. &gt
    3GPa), transformation to the primitive orthorhombic semimetal phase III occurs. This transformation from phase I to phase III is a pressure-induced first-order phase transition, which takes place through coherent sliding between weakly coupled layers. This structural phase transition is significantly influenced by Coulombic interactions in the geometric arrangement between interlayer Se ions. Furthermore, upon cooling, phase III transforms into the monoclinic phase IV, which is analogous to the excitonic insulator phase II. Finally, the excitonic interactions appear to be retained despite the observed layer sliding transition.

    DOI: 10.1107/S2052252517018334

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  49. Direct visualization of orbital flipping in volborthite by charge density analysis using detwinned data

    Kento Sugawara, Kunihisa Sugimoto, Tatsuya Fujii, Takafumi Higuchi, Naoyuki Katayama, Yoshihiko Okamoto, Hiroshi Sawa

    Journal of the Physical Society of Japan   Vol. 87 ( 2 )   2018.2

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    The distribution of d-orbital valence electrons in volborthite [Cu3V2O7(OH)212H2O] was investigated by charge density analysis of the multipole model refinement. Diffraction data were obtained by synchrotron radiation single-crystal X-ray diffraction experiments. Data reduction by detwinning of the multiple structural domains was performed using our developed software. In this study, using high-quality data, we demonstrated that the water molecules in volborthite can be located by the hydrogen bonding in cavities that consist of Kagome lattice layers of CuO4(OH)2 and pillars of V2O7. Final multipole refinements before and after the structural phase transition directly visualized the deformation electron density of the valence electrons. We successfully directly visualized the orbital flipping of the d-orbital dx2–y2, which is the highest level of 3d orbitals occupied by d9 electrons in volborthite. The developed techniques and software can be employed for investigations of structural properties of systems with multiple structural domains.

    DOI: 10.7566/JPSJ.87.024601

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  50. A novel red-emitting K2Ca(PO4)F:Eu2+ phosphor with a large Stokes shift

    H. Daicho, Y. Shinomiya, K. Enomoto, A. Nakano, H. Sawa, S. Matsuishi, H. Hosono

    Chemical Communications   Vol. 54 ( 8 ) page: 884 - 887   2018.1

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    We report a K2CaPO4F:Eu2+ phosphor with a new crystal structure. This phosphor has a large Stokes shift and converts near-ultraviolet light to red luminescence without absorption of other visible light. The mechanism was elucidated by applying a constrained density functional theory to the solved crystal structure.

    DOI: 10.1039/c7cc08202a

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  51. Investigation of Honeycomb Lattice Consisting of Cu-2(pymca)(3) Moieties Using Synchrotron Radiation X-ray Structure Analysis

    Kento Sugawara, Kunihisa Sugimoto, Naoyuki Katayama, Masayuki Hagiwara, Zentaro Honda, Hiroshi Sawa

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 86 ( 12 )   2017.12

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    We present structural studies of the spin-1/2 honeycomb-lattice antiferromagnet, Cu-2(pymca)(3)(ClO4) (pymca: pyrimidine-2-carboxylate), using synchrotron X-ray diffraction experiments. Previous research reported that its crystal structure consists of a regular honeycomb lattice, which exhibits quantum spin-liquid behavior. However, due to its threefold Cu2+ site symmetry, this proposed crystal structure cannot describe Jahn-Teller distortion. We analyzed the structure of Cu-2(pymca)(3)(ClO4), including superlattice reflections that were overlooked during previous X-ray diffraction studies of the material, and clarified that its distorted honeycomb lattice consists of Cu-2(pymca)(3) sections. Further investigation of Cu-2(pymca)(3)(ClO4) crystal structure may reveal magnetic susceptibilities of the distorted honeycomb lattice.

    DOI: 10.7566/JPSJ.86.123302

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  52. Nanocomposite Phosphor Consisting of CaI2:Eu2+ Single Nanocrystals Embedded in Crystalline SiO2

    Hisayoshi Daicho, Takeshi Iwasaki, Yu Shinomiya, Akitoshi Nakano, Hiroshi Sawa, Wataru Yamada, Satoru Matsuishi, Hideo Hosono

    ACS APPLIED MATERIALS & INTERFACES   Vol. 9 ( 47 ) page: 41405 - 41412   2017.11

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    High luminescence efficiency is obtained in halide- and chalcogenide-based phosphors, but they are impractical because of their poor chemical durability. Here we report a halide-based nanocomposite phosphor with excellent luminescence efficiency and sufficient durability for practical use. Our approach was to disperse luminescent single nanocrystals of caI(2):Eu2+ in a chemically stable, translucent crystalline SiO2 matrix. Using this approach, we successfully prepared a nanocomposite phosphor by means of self-organization through a simple solid-state reaction. Single nanocrystals of 6H polytype (thr notation) CaI2:Eu2+ with diameters of about SO rim could be generated not only in a SiO2 amorphous powder but also in a SiO2 glass plate. The nanocomposite phosphor formed upon solidification of molten CaI2 left behind in the crystalline SiO2 that formed from the amorphous SiO2 under the influence of a CaI2 flux effect. The resulting nanocomposite phosphor emitted brilliant blue luminescence with an internal quantum efficiency up to 98% upon 407 nm violet excitation. We used cathodoluminescence microscopy, scanning transmission electron microscopy, and Rietveld refinement of the X-ray diffraction patterns to confirm that the blue luminescence was generated only by the CaI2:Eu2+ single nanocrystals. The phosphor was chemically durable because the luminescence sites were embedded in the crystalline SiO2 matrix. The phosphor is suitable for use in near-ultraviolet light-emitting diodes. The concept for this nanocomposite phosphor can be expected to be effective for improvements in the practicality of poorly durable materials such as halides and chalcogenides.

    DOI: 10.1021/acsami.7b14132

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  53. Successive Dimensional Transition in (TMTTF)(2)PF6 Revealed by Synchrotron X-ray Diffraction

    Shunsuke Kitou, Tatsuya Fujii, Tadashi Kawamoto, Naoyuki Katayama, Sachiko Maki, Eiji Nishibori, Kunihisa Sugimoto, Masaki Takata, Toshikazu Nakamura, Hiroshi Sawa

    PHYSICAL REVIEW LETTERS   Vol. 119 ( 6 )   2017.8

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    A quasi-one-dimensional organic charge-transfer salt (TMTTF)(2)PF6 undergoes a multistep phase transition as the temperature decreases. One of these transitions is called a "structureless transition," and these detailed structures were unknown for many years. With synchrotron x-ray diffraction, we observed a slight structural difference owing to the effect of charge-order transition between two TMTTF molecules in a dimer, which corresponds to the charge transfer delta(CO) = 0.20e. The two-dimensional Wigner crystallization was determined from an electron density analysis using core differential Fourier synthesis. Furthermore, we found that the ground state due to tetramerization, called the spin Peierls phase, is a three-dimensional transition with interchain correlation.

    DOI: 10.1103/PhysRevLett.119.065701

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  54. Ising-like anisotropy stabilized (1)/(3) and (2)/(3) magnetization plateaus in the V3+ kagome lattice antiferromagnets Cs2KV3F12, Cs2NaV3F12, and Rb2NaV3F12

    Masato Goto, Hiroaki Ueda, Chishiro Michioka, Akira Matsuo, Koichi Kindo, Kento Sugawara, Shintaro Kobayashi, Naoyuki Katayama, Hiroshi Sawa, Kazuyoshi Yoshimura

    PHYSICAL REVIEW B   Vol. 95 ( 13 )   2017.4

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    We have investigated crystal structure and magnetic properties of three S = 1 V3+ Ising-like anisotropic kagome lattice antiferromagnets, Cs2KV3F12, Cs2NaV3F12, and Rb-2 NaV3F12, using single crystals. Each compound crystallizes in a monoclinic system and has a slightly distorted kagome lattice. Although the magnetic properties are similar, the details depend on the magnitude of magnetic anisotropy. The magnetization and magnetic susceptibility are highly anisotropic owing to anisotropic g factors and Ising-like single ion anisotropy originating from partially unquenched orbital moments of V3+, and the easy axis of Ising-like anisotropy is perpendicular to the kagome plane. In contrast to disordered ground states in the isostructural Ti3+ (S = 1/2) compounds, the V3+ (S = 1) compounds exhibit antiferromagnetic ordering with distorted 120 degrees. structure or other nearly coplanar magnetic structure whose basal spin plane includes the easy axis, which is mainly due to large magnetic anisotropy and decrease of quantum fluctuation. Moreover, when magnetic fields are applied perpendicular to the kagome plane, magnetization curves of them show distinct 1/3 and 2/3 magnetization plateaus, which are stabilized by Ising-like single ion anisotropy. In particular, the 2/3 magnetization plateaus are notable magnetic phenomena in kagome lattice antiferromagnets and are due to the combination of spin frustration, Ising-like single ion anisotropy, and the small monoclinic distortion of kagome lattices.

    DOI: 10.1103/PhysRevB.95.134436

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  55. Various Arsenic Network Structures in 112-Type Ca1-xLaxFe1-yPdyAs2 Revealed by Synchrotron X-ray Diffraction Experiments

    Shinya Tamura, Naoyuki Katayama, Yuto Yamada, Yuki Sugiyama, Kento Sugawara, Hiroshi Sawa

    INORGANIC CHEMISTRY   Vol. 56 ( 5 ) page: 3030 - 3035   2017.3

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    Two novel 112-type palladium-doped iron arsenides were synthesized and identified using comprehensive studies involving synchrotron X-ray diffraction and X-ray absorption near-edge structure (XANES) experiments. Whereas in-plane arsenic zigzag chains were found in the 112-type superconducting iron arsenide Ca1-xLaxFeAs2 with maximum T-c = 34 K, deformed arsenic network structures appeared in other 112-type materials, such as longitudinal arsenic zigzag chains in CaFe1-yPdyAs2 (y similar to 0.51) and arsenic square sheets constructed via hypervalent bonding in Ca1-xLaxFe1-yPdyAs2 (x similar to 0.31, y similar to 0.30). As K-edge XANES spectra clarified the similar oxidization states around FeAs4 tetrahedrons, alluding to possible parents for high-T-c 112-type iron arsenide superconductors.

    DOI: 10.1021/acs.inorgchem.6b03115

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  56. Iron arsenides with three-dimensional FeAs layer networks: Can(n+1)/2(Fe1-xPtx)(2+3n)Ptn(n-1)/2As(n+1)(n+2)/2 (n = 2, 3) Reviewed

    N. Katayama, S. Onari, K. Matsubayashi, Y. Uwatoko, and H. Sawa

    Scientific Reports   Vol. 6 ( 39280 )   2016.12

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    DOI: 10.1038/srep39280

  57. Importance of diffuse scattering for materials science Invited Reviewed

    Hiroshi Sawa

    IUCrJ     2016.9

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    DOI: 10.1107/S2052252516013889

  58. Absence of the static Jahn-Teller distortion in the copper oxide Ba3CuSb2O9 Reviewed

    N. Katayama, K. Kimura, Y. Han, J. Nasu, N. Drichko, Y. Nakanishi, Y. Ishiguro, R. Satake, E. Nishibori, M. Yoshizawa, T. Nakano, Y. Nozue, Y. Wakabayashi, S. Ishihara, M. Hagiwara, H. Sawa, and S. Nakatsuji

    Proc. Natl. Acad. Sci.   Vol. 112 ( 30 ) page: 9305-9309   2015.6

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    DOI: 10.1073/pnas.1508941112

  59. Synchrotron X-ray diffraction study of the Structural Phase Transition in Ca10(Ir4As8)(Fe2-xIrxAs2)5 Reviewed

    N. Katayama, K. Sugawara, Y. Sugiyama, T. Higuchi, K. Kudo, D. Mitsuoka, T. Mizokawa, M. Nohara, and H. Sawa

    J. Phys. Soc. Jpn.   Vol. 83   page: 113707   2014.10

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    DOI: http://dx.doi.org/10.7566/JPSJ.83.113707

  60. High Pressure Synthesis and Structural Characterization of the Type II Clathrate Compound Na30.5Si136 Encapsulating Two Sodium Atoms in the Same Silicon Polyhedral Cages Reviewed

    S. Yamanaka, M. Komatsu, M. Tanaka, H. Sawa and K. Inumaru

    J. Am. Chem. Soc   Vol. 136(21)   page: 7717-25   2014.5

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    DOI: 10.1021/ja502733e

  61. Observation of quadrupole helix chirality and its domain structure in DyFe3(BO3)4 Reviewed

    T. Usui, Y. Tanaka, H. Nakajima, M. Taguchi, A. Chainani, M. Oura, S. Shin, N. Katayama, H. Sawa, Y. Wakabayashi, and T. Kimura

    Nature Materials   Vol. 10   page: 611–618   2014.4

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    DOI: 10.1038/nmat3942

  62. Superconductivity in Ca1-xLaxFeAs2: A Novel 112-Type Iron Pnictide with Arsenic Zigzag Bonds Reviewed

    N. Katayama, K. Kudo, S. Onari, T. Mizukami, K. Sugawara, Y. Sugiyama, Y. Kitahama, K. Iba, K. Fujimura, N. Nishimoto, M. Nohara, and H. Sawa

    J. Phys. Soc. Jpn   Vol. 82   page: 123702   2013.11

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    DOI: 10.7566

  63. Superconductivity in Ca10(Ir4As8)(Fe2As2)5 with Square-Planar Coordination of Iridium Reviewed

    K. Kudo, D. Mitsuoka, M. Takasuga, Y. Sugiyama, K. Sugawara, N. Katayama, H. Sawa, H. S. Kubo, K. Takamori, M. Ichioka, T. Fujii, T. Mizokawa, and M. Nohara

    Scientific Reports   Vol. 3   page: 3101-1-5   2013.10

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    DOI: 10.1038/srep03101

  64. Quantum fluctuations in spin-ice-like Pr2Zr2O7 Reviewed

    K. Kimura, S. Nakatsuji, J-J. Wen, C. Broholm, M. B. Stone, E. Nishibori and H. Sawa

    Nature Communications   ( 4 )   2013.6

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    DOI: 10.1038/ncomms2914

  65. Structure of Tm@C82(I) Metallofullerene by Single-Crystal X-ray Diffraction Using the 1:2 Co-Crystal with Octaethylporphyrin Nickel (Ni(OEP)) Reviewed

    Yuki Sado, Shinobu Aoyagi, Ryo Kitaura, Yasumitsu Miyata, Eiji Nishibori, Hiroshi Sawa, Kunihisa Sugimoto, and Hisanori Shinohara

    Journal of Physical Chemistry C   Vol. 117   page: 6437-6442.   2013.3

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    DOI: 10.1021/jp311948c

  66. Room-temperature proton transport and its effect on thermopower in a solid ionic semiconductor, TTFCOONH4 Reviewed

    Yuka Kobayashi, Takenori Fujii,b Ichiro Terasaki,c Hiori Kino,a Yongcheng Jin,d Takashi Hibino,d Tetsuya Kobayashi,e Eiji Nishibori,e Hiroshi Sawa,e Hideki Yoshikawa,a Takeshi Terauchia and Satoshi Sumia

    Journal of Materials Chemistry A   Vol. 16   page: 5089-5096   2013.2

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    DOI: 10.1039/C3TA00011G

  67. Molecular Ionics in Supramolecular Assemblies with Channel Structures Reviewed

    Makoto Moriya,Hiro Kitaguchi,Eiji Nishibori, Hiroshi Sawa,Wataru Sakamoto, and Toshinobu Yogo

    CHEMISTRY   Vol. 18 ( 48 ) page: 15305-15309   2012.11

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    DOI: 10.1002/chem.201202056

  68. A novel phosphor for glareless white light-emitting diodes Reviewed

    Daicho H, Iwasaki T, Enomoto K, Sasaki Y, Maeno Y, Shinomiya Y, Aoyagi S, Nishibori E, Sakata M, Sawa H, Matsuishi S, Hosono H.

    Nature Communications   ( 3 )   2012.10

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    DOI: 10.1038/ncomms2138

  69. Spin-Orbital Short-Range Order on a Honeycomb-Based Lattice Reviewed

    S. Nakatsuji, K. Kuga, K. Kimura, R. Satake, N. Katayama, E. Nishibori, H. Sawa, R. Ishii, M. Hagiwara, F. Bridges, T. U. Ito, W. Higemoto, Y. Karaki, M. Halim, A. A. Nugroho, J. A. Rodriguez-Rivera, M. A. Green, C. Broholm

    Sciecne   Vol. 336 ( 4 ) page: 559-563   2012.5

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    DOI: 10.1126/science.1212154

  70. Spin-Orbital Short-Range Order on a Honeycomb-Based Lattice Reviewed

    S. Nakatsuji, K. Kuga, K. Kimura, R. Satake, N. Katayama, E. Nishibori, H. Sawa, R. Ishii, M. Hagiwara, F. Bridges, T. U. Ito, W. Higemoto, Y. Karaki, M. Halim, A. A. Nugroho, J. A. Rodriguez-Rivera, M. A. Green, C. Broholm

    Science   ( 336 )   2012.5

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    DOI: 10.1126/science.1212154

  71. A layered ionic crystal of polar Li@C60 superatoms Reviewed

    Shinobu Aoyagi1, Eiji Nishibori1, Hiroshi Sawa1, Kunihisa Sugimoto2,3, Masaki Takata2,3, Yasumitsu Miyata4, Ryo Kitaura4, Hisanori Shinohara4, Hiroshi Okada5, Takeshi Sakai5, Yoshihiro Ono5, Kazuhiko Kawachi5, Kuniyoshi Yokoo5, Shoichi Ono5, Kenji Omote5, Yasuhiko Kasama5, Shinsuke Ishikawa6, Takashi Komuro6 & Hiromi Tobita6

    nature chemistry2, published online:20 June2010   Vol. 2   page: 678-683   2010.6

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  72. Single-Component Molecular Conductor [Cu(tmdt)2] Containingan Antiferromagnetic Heisenberg Chain Reviewed

    Biao Zhou, Hiroyuki Yajima, Akiko Kobayashi, Yoshinori Okano, Hisashi Tanaka, Tetsuya Kumashiro, Eiji Nishibori, Hiroshi Sawa, and Hayao Kobayashi

    Inorganic Chemistry   Vol. 49 ( 14 ) page: 6740-6747   2010.4

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  73. Nitrated Benzyne Derivatives of La@C-82: Addition of NO2 and Its Positional Directing Effect on the Subsequent Addition of Benzynes Reviewed

    Lu X (Lu, Xing)1, Nikawa H (Nikawa, Hidefumi)1, Tsuchiya T (Tsuchiya, Takahiro)1, Akasaka T (Akasaka, Takeshi)1, Toki M (Toki, Makoto)2, Sawa H

    ANGEWANDTE CHEMIE-INTERNATIONAL EDITION&nbsp;&nbsp;&nbsp;&nbsp;   Vol. 49 ( 3 ) page: 594-597   2010

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  74. 放射光を用いた精密電子密度解析の現状と実際 Reviewed

    西堀英治, 澤 博

    固体物理   Vol. 44 ( 525 ) page: 35-51   2009.11

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    高輝度放射光による先端物性研究

  75. Organic Superconductivity Enhanced by Asymmetric-Anion Random Potential in (MDT-TS)I0.85Br0.41 [MDT-TS=5H-2-(1,3-diselenole-2-ylidene)-1,3,4,6-tetrathiapentalene] Reviewed

    Bando Y (Bando, Yoshimasa)1, Kawamoto T (Kawamoto, Tadashi)1, Mori T (Mori, Takehiko)1, Kakiuchi T (Kakiuchi, Toru)2, Sawa H (Sawa, Hiroshi)2,3, Takimiya K (Takimiya, Kazuo)4, Otsubo T (Otsubo, Tetsuo)4

    CHEMISTRY OF MATERIALS&nbsp;&nbsp;&nbsp;&nbsp;   Vol. 21 ( 15 ) page: 3521-3525   2009.8

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  76. Rotational Sublevels of an Ortho-Hydrogen Molecule Encapsulated in an Isotropic C60 Cage Reviewed

    Yoshimitsu Kohama, Takeshi Rachi, Ju Jing, Zhaofei Li, Jun Tang, Ryotaro Kumashiro, Satoru Izumisawa, Hitoshi Kawaji, Tooru Atake, Hiroshi Sawa, Yasujiro Murata, Koichi Komatsu, and Katsumi Tanigaki

    Physical Review Letters   ( 103 ) page: 073001-1~4   2009.8

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    DOI: 10.1103/PhysRevLett.103.073001

  77. Size of orbital-ordering domain controlled by the itinerancy of the 3d electrons in a manganite thin film Reviewed

    Y. Wakabayashi, H. Sagayama, T. Arima, M. Nakamura*, Y. Ogimoto, Y. Kubo, K. Miyano and H. Sawa

    Physical Review B   Vol. 79   page: 220403-1-220403-4   2009.6

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  78. Structural study on Pr-0.55(Ca1-ySry)(0.45)MnO3 thin films on perovskite (011) substrate Reviewed

    Wakabayashi Y (Wakabayashi, Y.)1, Takubo N (Takubo, N.)2, Miyano K (Miyano, K.)2,3, Sawa H (Sawa, H.)4

    EUROPEAN PHYSICAL JOURNAL-SPECIAL TOPICS&nbsp;&nbsp;&nbsp;&nbsp;   Vol. 167   page: 67-71   2009.2

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  79. Crystal Structure and Valence Distribution of [(LaMnO3)(m)(SrMnO3)(m)](n) Artificial Superlattices Reviewed

    Nakao H (Nakao, Hironori)1, Nishimura J (Nishimura, Jun)1, Murakami Y (Murakami, Youichi)1, Ohtomo A (Ohtomo, Akira)2, Fukumura T (Fukumura, Tomoteru)2, Kawasaki M (Kawasaki, Masashi)2, Koida T (Koida, Takashi)3, Wakabayashi Y (Wakabayashi, Yusuke), Sawa H (Sawa, Hiroshi)4

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN&nbsp;&nbsp;&nbsp;&nbsp;   Vol. 78 ( 2 )   2009.2

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  80. A gradational system for ferroelectric nanosized (Pb0.7Sr0.3)TiO3 particles Reviewed

    Fumihito Shikanai, Jun Kano, Hiroshi Sawa, Fan Zhang, Tomoaki Karaki, Masatoshi Adachi, Je-Geun Park, Seiji Kojima, Susumu Ikeda and Takeshi Kamiyama

    Journal of Physics: Condensed Matter   Vol. 21   page: 025903 -1-025903 -6   2009.1

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  81. Bis-Carbene Adducts of Non-IPR La2@C72 : Localization of High Reactivity around Fused Pentagons and Electrochemical Properties Reviewed

    Xing Lu, Hidefumi Nikawa, Takahiro Tsuchiya, Yutaka Maeda, Midori O. Ishitsuka,Takeshi Akasaka,* Makoto Toki, Hiroshi Sawa, Zdenek Slanina, Naomi Mizorogi, and Shigeru Nagase

    Angewandte Chemie International Edition   Vol. 47   page: 8642-8645   2008.10

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  82. Chemical understanding of a non-IPR metallofullerene: Stabilization of encaged metals on fused-pentagon bonds in La-2@C-72 Reviewed

    Lu X (Lu, Xing)1, Nikawa H (Nikawa, Hidefumi)1, Nakahodo T (Nakahodo, Tsukasa)1, Tsuchiya T (Tsuchiya, Takahiro)1, Ishitsuka MO (Ishitsuka, Midori O.)1, Maeda Y (Maeda, Yutaka)2, Akasaka T (Akasaka, Takeshi)1, Toki M (Toki, Makoto)3, Sawa H (Sawa, Hiroshi)3, Slanina Z (Slanina, Zdenek)1, Mizorogi N (Mizorogi, Naomi)4, Nagase S (Nagase, Shigeru)4

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY&nbsp;&nbsp;&nbsp;&nbsp;   Vol. 130 ( 28 ) page: 9129-9136   2008.7

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  83. Numerical computation of radiative heating environment for Huygens probe entry flight Reviewed

    Sawa H (Sawa, Hiroshi)1, Matstryama S (Matstryama, Shingo)2, Ohnishi N (Ohnishi, Naofumi)1, Furudate M (Furudate, Michiko)1, Sawada K (Sawada, Keisuke)1

    JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER&nbsp;&nbsp;&nbsp;&nbsp;   Vol. 22 ( 2 ) page: 140-149   2008.4

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  84. Addition of adamantylidene to La-2@C-78: Isolation and single-crystal X-ray structural determination of the monoadducts Reviewed

    Cao B (Cao, Baopeng)1, Nikawa H (Nikawa, Hidefumi)1, Nakahodo T (Nakahodo, Tsukasa)1, Tsuchiya T (Tsuchiya, Takahiro)1, Maeda Y (Maeda, Yutaka)2,3, Akasaka T (Akasaka, Takeshi)1, Sawa H (Sawa, Hiroshi)4, Slanina Z (Slanina, Zdenek)1, Mizorogi N (Mizorogi, Naomi)5, Nagase S (Nagase, Shigeru)5

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY&nbsp;&nbsp;&nbsp;&nbsp;   Vol. 130 ( 3 ) page: 983-989   2008.1

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  85. Orbital Ordering Structures in (Nd,Pr)0.5Sr0.5MnO3 Manganite Thin Films on Perovskite (011) Substrates Reviewed

    Yusuke Wakabayashi, Daisuke Bizen, Yugo Kubo, Hironori Nakao, Youichi Murakami, Masao Nakamura, Yasushi Ogimoto, Kenjiro Miyano, and Hiroshi Sawa

    J.Phys.Soc.Jpn.   Vol. 77 ( 1 ) page: 014712-1 – 014712-7   2008

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  86. 分子性伝導体におけるWigner結晶の観測―幾何学フラストレーションと秩序変数― Reviewed

    澤博、鹿野田一司

    固体物理   Vol. 42 ( 12 ) page: 39 (911)-52 (924)   2007.12

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  87. *Charge ordering in α-(BEDT-TTF)2I3 by synchrotron X-ray diffraction Reviewed

    T.Kakiuchi, Y. Wakabayashi, H. Sawa, T. Takahashi, and T. Nakamura

    J. Phys. Soc. Jpn.   Vol. 76   page: 113702   2007.11

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  88. Relation between superconductivity and superstructure in Ce2RhIn8 Reviewed

    Masahito Koeda, Tetsuya Fujiwara, Masato Hedo, Yoshiya Uwatoko, Hajime Sagayama, Yusuke Wakabayashi and Hiroshi Sawa

    Journal of Magnetism and Magnetic Materials   Vol. 310,Issue2,Part1   page: e31-e32   2007.3

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  89. *Wigner Crystallization in (DI-DCNQI)2Ag Detected by Synchrotron Radiation X-Ray Diffraction Reviewed

    T. Kakiuchi,Y. Wakabayashi, H. Sawa,T. Itou, K. Kanoda

    Phys Rev. Lett.   Vol. 98   page: 066402-1-066402-4   2007.2

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  90. Superconductivity of doped Ar@C60 Reviewed

    K. Yakigaya, A. Takeda, Y. Yokoyama, S. Ito, T. Miyazaki, T. Suetsuna, H. Shimotani, T. Kakiuchi, H. Sawa, H. Takagi, K. Kitazawa, N. Dragoe

    New Journal of Chemistry   Vol. 31   page: 973-979   2007

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  91. X-ray Diffraction Study on Charge and Orbital Order in Pr0.65Ca0.35MnO3 under High Pressure Reviewed

    Susumu Shimomura, Kazutoshi Torashima, Nobuyoshi Wakabayashi, Kengo Nishimoto, Takashi Tonegawa, Nozomu Hamaya, Hiroshi Sawa, Yasuhide Tomioka, and Yoshinori Tokura

    J.Phys. Soc.Jpn.   Vol. 76 ( 12 ) page: 124603-1-12463-6   2007

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  92. Manganese (III, IV) and Manganese (III) Oxide Clusters Trapped by Copper (II) Complexes Reviewed

    S. Yamashita, T .Shiga, M. Kurashima, M. Nihei, H. Nojiri, H. Sawa, T. Kakiuchi, H. Oshio

    Inorganic Chemistry   Vol. 46 ( 10 ) page: 3810-3812 (2007)   2007

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  93. Domain formation in the structural phase transition of the organic superconductor κL-(DMEDO-TSeF)2[Au(CN)4](THF) Reviewed

    T. Kawamoto, T. Mori, T. Kakiuchi, H. Sawa, T. Shirahata, M. Kibune, H. Yoshino, and T. Imakubo

    Phys. Rev. B   Vol. 76   page: 134517   2007

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  94. Pressure-Induced Metal-Semiconductor-Metal Transitions in an MMX-Chain Complex, Pt2(C2H5CS2)4I Reviewed

    A. Kobayashi, A. Tokunaga, R. Ikeda, H. Sagayama, Y. Wakabayashi, H. Sawa, M. Hedo, Y. Uwatoko, and H. Kitagawa

    European Journal of Inorganic Chemistry     page: 3567-3570   2006.9

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  95. Current-Induced metallic State in an Organic (EDT-TSF)2 GaCl4 Conductor. Reviewed

    H. Endo, T. Kawamoto, T. Mori, I. Terasaki, T. Kakiuchi, H. Sawa, M. Kodani, K. Takimiya, and T. Otsubo

    J. Am. Chem. Soc.   Vol. 128   page: 9006-9007   2006.7

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  96. Most Stable Metallic Phase of the Mixed-Valence MMX-Chain, Pt2(dtp)4I (dtp:C2H5CS2-), in Purely d-Electronic Conductors Based on the Transition-Metal Complex. Reviewed

    K.Otsubo, A.Kobayashi, H. Kitagawa, M.Hedo, Y.Uwatoko, H.Sagayama, Y.Wakabayashi and H.Sawa.

    J. Am. Chem. Soc.   Vol. 128   page: 8140-8141   2006.6

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  97. Dynamical Valence Fluctuation at the Charge-Density-Wave Phase Boundary in Iodide-Bridged Pt Compound [Pt(chxn)2I]I2., Reviewed

    S. Takaishi, D. Kawakami, M. Yamashita, M. Sasaki, T. Kajiwara, H. Miyasaka, K. Sugiura, Y. Wakabayashi, H. Sawa, H. Matsuzaki, H. Kishida, H. Okamoto, H. Watanabe, H. Tanaka, K. Marumoto, H. Ito, and S. Kuroda.

    J. Am. Chem. Soc.   Vol. 128 ( 19 ) page: 6420-6425   2006.5

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  98. *Direct Determination of Low-Dimensional Structures: Synchrotron X-ray Scattering on One-Dimensional Charge-Ordered MMX-Chain Complexes. Reviewed

    Y. Wakabayashi, A. Kobayashi, H. Sawa, H. Ohsumi, N. Ikeda, and H. Kitagawa.

    J. Am. Chem. Soc.   Vol. 128   page: 6676-6682   2006.5

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  99. *Two Types of Multistack Structures in MgB2-Type Superconductor CaAlSi. Reviewed

    H. Sagayama, Y. Wakabayashi, H. Sawa, T. Kamiyama, A. Hoshikawa, S. Hatjo, K. Uozato, A. K. Ghosh, M. Tokunaga, T. Tamegai.

    J. Phys. Soc. Jpn.   Vol. 75   page: 043713-1-043713-4   2006.4

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  100. Iron Vacancy Ordered γ-Fe2O3(001) Epitaxial Films: The Crystal Structure and Electrical Resistivity. Reviewed

    H. Yanagihara, M. Hasegawa, E. Kita, Y. Wakabayashi, H. Sawa, and K. Siratori.

    J. Phys. Soc. Jpn.   Vol. 75 ( 5 ) page: 054708-1-054708-5   2006.3

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  101. Novel orbital ordering induced by anisotropic stress in a manganite thin film. Reviewed

    Wakabayashi, D. Bizen, H. Nakao, Y. Murakami, M. Nakamura, Y. Ogimoto, K. Miyano and H. Sawa.

    Phys Rev. Lett.   Vol. 96 ( 1 ) page: 017202-1-017202-4   2006.1

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  102. Correlation between crystal structures of CaAlSi with and without superlattice and superconduction properties. Reviewed

    S. Kuroiwa, H. Sagayama, T. Kakiuchi, H. Sawa, Y. Noda, and J. Akimitsu.

    Phys. Rev. B   Vol. 74   page: 014517-1-014517-5   2006

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  103. Halogen-Bridged PtII/PtIV Mixed-Valence Ladder Compounds Reviewed

    D. Kawakami, M. Yamashita,* S. Matsunaga, S. Takeishi, T. Kajiwara, H. Miyasaka, K. Sugiura, H. Matsuzaki, H. Okamoto, Y. Wakabayashi, H. Sawa

    Angewandte Chemie Int. Ed.   Vol. 45   page: 7214-7217   2006

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  104. Checkerboard-type charge-ordered state of a pressure-induced superconductor, β-(meso-DMBEDT-TTF)2PF6 Reviewed

    S. Kimura, H. Suzuki, T. Maejima, H. Mori, J.-I. Yamaura, T. Kakiuchi, H. Sawa, H. Moriyama.

    J. Am. Chem. Soc.   Vol. 128   page: 1456-1457   2006

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  105. Superconductivity of doped Ar@C60., Reviewed

    A. Takeda, Y. Yokoyama, S. Ito, T. Miyazaki, H. Shimotani, K. Yakigaya, T. Kakiuchi, H. Sawa, H. Takagi, K. Kitazawa and N. Dragoe.

    Chem. Commun.   Vol. 8   page: 912-914   2006

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  106. Clamp-Type Pressure Cell for Full Strcture Determination of Molecular Single Crystals up to 1.5 GPa Reviewed

    T.Hasegawa, R.Kumai, Y.Takahashi, Y.Tokura and H.Sawa

    Rev.Sci.Instrum.   Vol. 76   page: 073903   2005.7

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  107. Periodic Arrangement of Quadrupolar Moments Induced by the Antiferromagnetic Order in TbB2C2: Observation by Resonant X-ray Scattering Reviewed

    D. Okuyama, T. Matsumura, H. Nakao, Y. Murakami, H. Onodera, A. Tobo, Y. Wakabayashi and H. Sawa

    J. Phys. Soc. Jpn.   Vol. 74 ( 5 ) page: 1566-1571   2005.5

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  108. Resonant x-ray scattering on antiferroquadrupolar ordering compound Dy0.8Gd0.2B2C2 Reviewed

    M. Sakata, A. Tobo, T. Matsumura, D. Okuyama, Y. Murakami, Y. Wakabayashi, H. Sawa, K. Ohoyama and H. Onodera

    Physica B   Vol. 359   page: 950-952   2005.4

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  109. *Floating Single Hydrogen Molecule in an Open-Cage Fullerene Reviewed

    H. Sawa, Y. Wakabayashi, Y. Murata, M. Murata, and K. Komatsu

    Angewandte Chemie   Vol. 44 ( 13 ) page: 1981-1983   2005

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Books 7

  1. 分子性物質の物理 -物性物理の新潮流-

    鹿野田一司・宇治進也 編 ( Role: Joint author)

    朝倉書店  2015.10  ( ISBN:978-4-254-13119-2

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    Language:Japanese

  2. 物質科学の基礎

    那須奎一郎、澤 博、門野良典( Role: Joint author)

    共立出版  2012.4  ( ISBN:978-4-320-03488-4

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    大学院進学を目指す学生に対して、固体物理の基本原理から最先端研究への視点を明らかにする

  3. 大学院講義 物理化学 第2版 III. 固体の化学と物性

    倖田清一郎、小谷正博、染田清彦、阿波賀邦夫編、澤博、他( Role: Joint author)

    東京化学同人  2012.3  ( ISBN:978-4-8079-0771-7

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    放射光X線を用いた構造解析の最先端手法についての解説

  4. Molecular Electronic and Related Materials-Control and Probe with Light 2010(5.Study of the novel aharge ordering state in molecular conductors using synchrotron radiation X-ray diffraction)

    Editor:Toshio NaitoHiroshi Sasa,Toru Kakiuchi( Role: Joint author)

    TRANSWORLD RESEARCH NETWORK  2010 

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    Language:English

  5. 配位空間の化学‐最新技術と応用‐(水素吸蔵体の構造決定‐放射光X線回析による電子密度解析の 最先端-)

    北川 進 他47名( Role: Joint author)

    株式会社 シーエムシー出版  2009.10 

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  6. 第5版 実験化学講座電気物性,磁気物性

    中村敏和他 50名( Role: Joint author)

    丸善株式会社  2004.3 

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  7. 第5版 実験化学講座基礎編Ⅲ 物理化学下

    古川行夫 他8名( Role: Joint author)

    丸善株式会社  2003.10 

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MISC 55

  1. Direct observation of short-range orbital order in pyrochlore-type oxide Y<sub>2</sub>Mo<sub>2</sub>O<sub>7</sub> by resonant soft X-ray scattering experiments

    鬼頭俊介, 福田光, 上田健太郎, 金子良夫, 原武史, 澤博, 山崎裕一, 中尾裕則, 十倉好紀, 十倉好紀, 有場孝尚, 有場孝尚

    日本物理学会講演概要集(CD-ROM)   Vol. 78 ( 1 )   2023

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  2. Structure and electron phase of a series of one-dimensional organic conductors (TMTTF)<sub>2</sub>X salts

    中村敏和, 古川貢, 古川貢, 鬼頭俊介, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 77 ( 1 )   2022

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  3. Generalized phase-diagram of 1D organic conductors (TMTTF)<sub>2</sub>X: Structure and electronic phase

    中村敏和, 古川貢, 鬼頭俊介, 澤博

    分子科学討論会講演プログラム&要旨(Web)   Vol. 16th   2022

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  4. Observation of one-dimensional short-range orbital order in spin-glass pyrochlore Y<sub>2</sub>Mo<sub>2</sub>O<sub>7</sub> by X-ray diffuse scattering analysis using a single crystal

    鬼頭俊介, 福田光, 上田健太郎, 金子良夫, 細木雄斗, 澤博, 中村唯我, 杉本邦久, 十倉好紀, 十倉好紀, 有馬孝尚, 有馬孝尚

    日本物理学会講演概要集(CD-ROM)   Vol. 77 ( 2 )   2022

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  5. Observation of X-ray diffuse scattering in pyrochlore-type oxide Y<sub>2</sub>Mo<sub>2</sub>O<sub>7</sub> using synchrotron radiation

    鬼頭俊介, 細木雄斗, 福田光, 上田健太郎, 金子良夫, 山崎裕一, 中尾裕則, 十倉好紀, 十倉好紀, 澤博, 有馬孝尚, 有馬孝尚

    日本物理学会講演概要集(CD-ROM)   Vol. 77 ( 1 )   2022

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  6. Observation of phonon dynamics in spin-glass pyrochlore Y<sub>2</sub>Mo<sub>2</sub>O<sub>7</sub> by inelastic X-ray scattering experiments

    鬼頭俊介, 森仁志, 福田光, 上田健太郎, 金子良夫, 原武史, 澤博, 佐賀山基, 萬條太駿, 石川大介, 石川大介, BARON A. Q. R., BARON A. Q. R., 有田亮太郎, 有田亮太郎, 十倉好紀, 十倉好紀, 有馬孝尚, 有馬孝尚

    日本物理学会講演概要集(CD-ROM)   Vol. 77 ( 2 )   2022

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  7. Hall effect measurement of narrow gap semiconductor Ta<sub>2</sub>NiS<sub>5</sub> under pressure

    有馬寛人, 片山尚幸, 澤博, 野原実, LU Y. F., 北川健太郎, 高木英典, 高木英典, 上床美也, 松林和幸

    日本物理学会講演概要集(CD-ROM)   Vol. 76 ( 2 )   2021

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  8. Responses to an intense THz electric-field pulse in an excitonic insulator Ta<sub>2</sub>NiSe<sub>5</sub>: III

    高村直幹, 斎藤真幸, LIANG S., 大瀧貴史, 宮本辰也, 水井誠, 貴田徳明, 中埜彰俊, 澤博, 岡本博, 岡本博

    日本物理学会講演概要集(CD-ROM)   Vol. 76 ( 1 )   2021

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  9. Direct observation of Mo-4d and Nd-4f orbital electrons in pyrochlore oxide Nd<sub>2</sub>Mo<sub>2</sub>O<sub>7</sub>

    鬼頭俊介, 金子良夫, 野村悠祐, 有田亮太郎, 有田亮太郎, 十倉好紀, 十倉好紀, 澤博, 有馬孝尚, 有馬孝尚

    日本物理学会講演概要集(CD-ROM)   Vol. 76 ( 2 )   2021

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  10. 放射光X線回折を用いた3d電子軌道の直接観測

    鬼頭俊介, 萬條太駿, 片山尚幸, 獅子堂達也, 有馬孝尚, 有馬孝尚, 出口康二郎, 十倉好紀, 十倉好紀, 杉本邦久, 澤博

    日本放射光学会年会・放射光科学合同シンポジウム(Web)   Vol. 34th   2021

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  11. Study of electronic states of α-(BETS)<sub>2</sub>I<sub>3</sub> by X-ray diffraction and first-principles calculations

    澤博, 鬼頭俊介, 圓谷貴夫, 開康一, 中村敏和

    日本物理学会講演概要集(CD-ROM)   Vol. 75 ( 1 )   2020

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  12. First-principles study on 3d orbital state in spinel oxide FeV<sub>2</sub>O<sub>4</sub> with Fe and V having orbital degree of freedom

    野村悠祐, 萬條太駿, 澤博, 有田亮太郎, 有田亮太郎

    日本物理学会講演概要集(CD-ROM)   Vol. 75 ( 2 )   2020

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  13. Observation of 3d orbital state in spinel oxide FeV<sub>2</sub>,O<sub>4</sub> with Fe and V having orbital degree of freedom

    萬條太駿, 鬼頭俊介, 片山尚幸, 野村悠祐, 有田亮太郎, 有田亮太郎, 新居陽一, 新居陽一, 有馬孝尚, 有馬孝尚, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 75 ( 2 )   2020

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  14. Direct observation of 3d orbital state in RTiO<sub>3</sub> by core differential Fourier synthesis method using synchrotron X-ray

    鬼頭俊介, 萬條太駿, 片山尚幸, 獅子堂達也, 有馬孝尚, 有馬孝尚, 田口康二郎, 十倉好紀, 十倉好紀, 杉本邦久, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 75 ( 2 )   2020

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  15. Spin-orbit coupling effect on Dirac band dispersions in quasi-2D molecular conductor α-(BETS)<sub>2</sub>I<sub>3</sub>

    圓谷貴夫, 鬼頭俊介, 澤端日華瑠, 石井史之, 鈴村順三, 開康一, 中村敏和, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 75 ( 2 )   2020

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  16. Effect of intense THz electric field in excitonic insulator Ta<sub>2</sub>NiSe<sub>5</sub>: II

    高村直幹, 西澤葉, 鈴木博貴, LIANG S., 近藤秋洋, 大瀧貴史, 宮本辰也, 水井誠, 貴田徳明, 中埜彰俊, 澤博, 岡本博, 岡本博

    日本物理学会講演概要集(CD-ROM)   Vol. 75 ( 1 )   2020

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  17. Direct observation of valence electron density distribution in RTiO<sub>3</sub> using core differential Fourier synthesis method

    鬼頭俊介, 萬條太駿, 片山尚幸, 獅子堂達也, 有馬孝尚, 有馬孝尚, 田口康二郎, 十倉好紀, 十倉好紀, 横山利彦, 中村敏和, 杉本邦久, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 75 ( 1 )   2020

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  18. Ta<sub>2</sub>NiSe<sub>5</sub>における光誘起励起子絶縁体相融解のダイナミクスと励起光子密度依存性

    宮本辰也, 水井誠, 平田純也, 山川大路, 森本剛史, 貴田徳明, 中埜彰俊, 澤博, 岡本博, 岡本博

    日本物理学会講演概要集(CD-ROM)   Vol. 74 ( 1 )   2019

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  19. Ruddlesden-Popper型酸化物Li<sub>2</sub>SrNb<sub>2</sub>O<sub>7</sub>における誘電物性

    永井隆之, 中埜彰俊, 森分博紀, 澤博, 寺崎一郎, 谷口博基

    日本物理学会講演概要集(CD-ROM)   Vol. 74 ( 1 )   2019

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  20. 励起子絶縁体Ta<sub>2</sub>NiSe<sub>5</sub>の高強度テラヘルツ電場応答

    高村直幹, LIANG S., 宮本辰也, 水井誠, 貴田徳明, 中埜彰俊, 澤博, 岡本博, 岡本博

    日本物理学会講演概要集(CD-ROM)   Vol. 74 ( 2 )   2019

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  21. 高圧下におけるTa<sub>2</sub>NiSe<sub>5</sub>の輸送特性

    有馬寛人, 内藤康氏, 工藤一輝, 片山尚幸, 澤博, 野原実, LU Y. F., 北川健太郎, 高木英典, 高木英典, 上床美也, 松林和幸

    日本物理学会講演概要集(CD-ROM)   Vol. 74 ( 1 )   2019

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  22. βパイロクロア酸化物CsW<sub>2</sub>O<sub>6</sub>単結晶の合成と物性 III

    三十日陸斗, 二木健太, 岡本佳比古, 長谷川巧, 荻田典男, 天野春樹, 片山尚幸, 澤博, 竹中康司

    日本物理学会講演概要集(CD-ROM)   Vol. 73 ( 1 ) page: ROMBUNNO.25aK404‐6   2018.3

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    J-GLOBAL

  23. Cu<sub>x</sub>TiSe<sub>2</sub>単結晶を用いた構造物性研究

    鬼頭俊介, 小林慎太郎, 片山尚幸, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 73 ( 1 ) page: ROMBUNNO.22aK402‐7   2018.3

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    J-GLOBAL

  24. 1T‐TiSe<sub>2</sub>の高圧低温下における光学伝導度と電子状態

    岡村英一, 坪内厚志, 片山尚幸, 澤博, 池本夕佳, 森脇太郎

    日本物理学会講演概要集(CD-ROM)   Vol. 73 ( 1 ) page: ROMBUNNO.22aK402‐8   2018.3

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    J-GLOBAL

  25. 放射光X線を用いた異常原子価のCrをもつCrSe<sub>2</sub>の構造物性研究

    小林慎太郎, 片山尚幸, 道岡千城, 植田浩明, 吉村一良, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 73 ( 1 ) page: ROMBUNNO.24pK503‐2   2018.3

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    J-GLOBAL

  26. 放射光X線を用いた二次元三角格子系LiVS<sub>2</sub>におけるV三量体構造の観測

    田村慎也, 山本暖, 片山尚幸, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 73 ( 1 ) page: ROMBUNNO.22aK403‐4   2018.3

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    J-GLOBAL

  27. 層状Li<sub>0.33</sub>VS<sub>2</sub>における巨大なエントロピー変化を伴う構造相転移

    片山尚幸, 田村慎也, 山口伴紀, 杉本高大, 太田幸則, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 73 ( 1 ) page: ROMBUNNO.22aK403‐5   2018.3

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  28. ポンプ‐プローブ分光によるTa<sub>2</sub>NiSe<sub>5</sub>の励起子絶縁体相融解ダイナミクスの研究 II

    水井誠, 宮本辰也, 平田純也, 森本剛史, 山川大路, 貴田徳明, 中埜彰俊, 澤博, 岡本博, 岡本博

    日本物理学会講演概要集(CD-ROM)   Vol. 73 ( 1 ) page: ROMBUNNO.24pK502‐8   2018.3

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  29. コア差フーリエ合成解析によるFeV<sub>2</sub>O<sub>4</sub>の軌道秩序の観測

    萬條太駿, 菅原健人, 鬼頭俊介, 片山尚幸, 新居陽一, 有馬孝尚, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 73 ( 1 ) page: ROMBUNNO.22aK403‐6   2018.3

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  30. S=1/2カゴメ格子反強磁性体Cs<sub>2</sub>ATi<sub>3</sub>F<sub>12</sub>(A<sup>+</sup>=Li<sup>+</sup>,Na<sup>+</sup>,K<sup>+</sup>,Rb<sup>+</sup>,NH<sup>+</sup><sub>4</sub>)の構造歪みと物性

    白上龍, 後藤真人, 植田浩明, 小林慎太郎, 菅原健人, 片山尚幸, 澤博, 松尾晶, 金道浩一, 道岡千城, 吉村一良

    日本物理学会講演概要集(CD-ROM)   Vol. 73 ( 1 ) page: ROMBUNNO.23aK305‐7   2018.3

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  31. 混合配位子場を有する近紫外光を可視光変換する蛍光体の結晶構造解析

    中埜彰俊, 澤博, 榎本公典, 四ノ宮裕, 大長久芳, 松石聡, 細野秀雄

    日本物理学会講演概要集(CD-ROM)   Vol. 73 ( 1 ) page: ROMBUNNO.24pK506‐6   2018.3

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  32. ポンプ-プローブ分光によるTa<sub>2</sub>NiSe<sub>5</sub>の励起子絶縁体相融解ダイナミクスの研究 III

    水井誠, 宮本辰也, 平田純也, 山川大路, 森本剛史, 貴田徳明, 中埜彰俊, 澤博, 岡本博, 岡本博

    日本物理学会講演概要集(CD-ROM)   Vol. 73 ( 2 )   2018

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  33. Ta<sub>2</sub>NiSe<sub>5</sub>の圧力誘起層スライド転移

    中埜彰俊, 菅原健人, 田村慎也, 片山尚幸, 松林和幸, 岡田卓, 上床美也, 宗像孝司, 中尾朗子, 佐賀山基, 熊井玲児, 前島尚行, 町田晃彦, 綿貫徹, 澤博

    高圧討論会講演要旨集   Vol. 58th   page: 133   2017.10

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  34. 複数結晶を用いた放射光X線単結晶回折による高圧極低温下高精度構造解析

    鬼頭俊介, 菅原健人, 中埜彰俊, 片山尚幸, 前島尚行, 町田晃彦, 綿貫徹, 澤博

    高圧討論会講演要旨集   Vol. 58th   page: 147   2017.10

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  35. 高圧下TiSe<sub>2</sub>の光学スペクトルおよび電子状態

    岡村英一, 坪内厚志, 片山尚幸, 澤博, 池本夕佳, 森脇太郎

    高圧討論会講演要旨集   Vol. 58th   page: 181   2017.10

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  36. α‐ET<sub>2</sub>I<sub>3</sub>の電荷秩序から始まった分子性結晶の電子状態の直接観測

    澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 2 ) page: ROMBUNNO.23aC20‐1   2017.9

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  37. 2つの単結晶を用いた放射光X線回折による1T‐TiSe<sub>2</sub>の高圧極低温下構造解析

    鬼頭俊介, 菅原健人, 中埜彰俊, 片山尚幸, 金子竜也, 前島尚行, 町田晃彦, 綿貫徹, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 2 ) page: ROMBUNNO.21aF31‐4   2017.9

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  38. 放射光X線による分子性結晶の精密電子密度解析

    鬼頭俊介, 杉本邦久, 中村敏和, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 2 ) page: ROMBUNNO.22aPS‐33   2017.9

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  39. 励起子絶縁体候補物質Ta<sub>2</sub>NiSe<sub>5</sub>の放射光X線非弾性散乱 II

    中埜彰俊, 田村慎也, 片山尚幸, 長谷川巧, 筒井智嗣, 松石聡, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 2 ) page: ROMBUNNO.23aPS‐113   2017.9

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  40. フッ酸溶液を用いて合成した新規カゴメ格子反強磁性体A<sub>2</sub>BTi<sub>3</sub>F<sub>12</sub>の物性

    白上龍, 植田浩明, 小林慎太郎, 菅原健人, 片山尚幸, 澤博, 道岡千城, 吉村一良

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 2 ) page: ROMBUNNO.22aE20‐8   2017.9

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  41. カゴメ弗化物A<sub>2</sub>BM<sub>3</sub>F<sub>12</sub>(A,B:アルカリ金属,M:3d遷移金属)の構造物性研究

    小林慎太郎, 菅原健人, 後藤真人, 白上龍, 道岡千城, 植田浩明, 吉村一良, 片山尚幸, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 2 ) page: ROMBUNNO.21aPS‐56   2017.9

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  42. β‐パイロクロア型CsW<sub>2</sub>O<sub>6</sub>における散漫散乱と多段階構造相転移

    天野春樹, 二木健太, 三十日陸斗, 岡本佳比古, 竹中康司, 片山尚幸, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 2 ) page: ROMBUNNO.22pF31‐12   2017.9

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  43. β型パイロクロア酸化物CsW<sub>2</sub>O<sub>6</sub>単結晶の合成と物性 II

    二木健太, 岡本佳比古, 天野春樹, 片山尚幸, 澤博, 中村優斗, 岸田英夫, 竹中康司

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 1 ) page: ROMBUNNO.19pL22‐6   2017.3

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  44. Mo二量体を持つルチル型Li<sub>x</sub>MoO<sub>2</sub>の構造相転移と物性

    山田悠人, 田村慎也, 片山尚幸, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 1 ) page: ROMBUNNO.18pL22‐12   2017.3

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  45. KDPのX線非弾性散乱

    宇田川眞行, 長谷川巧, 生見健太, 荻田典男, 筒井智嗣, 安居院あかね, 鬼頭俊介, 澤博, 冨永靖徳

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 1 ) page: ROMBUNNO.17pC44‐10   2017.3

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  46. 放射光X線回折によるスピン1/2ハニカム格子系Cu<sub>2</sub>(pymca)<sub>3</sub>(ClO<sub>4</sub>)の構造解析

    菅原健人, 片山尚幸, 奥谷顕, 木田孝則, 鳴海康雄, 萩原政幸, 本多善太郎, 佐賀山基, 熊井玲児, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 1 ) page: ROMBUNNO.17pC36‐8 - 1076   2017.3

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    DOI: 10.11316/jpsgaiyo.72.1.0_1076

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  47. 放射光X線による擬一次元分子性導体(TMTTF)<sub>2</sub>PF<sub>6</sub>の構造物性研究

    鬼頭俊介, 中村敏和, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 1 ) page: ROMBUNNO.20aC21‐3   2017.3

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  48. 多彩なヒ素ネットワーク構造を持つ112型鉄ヒ化物の構造物性研究

    片山尚幸, 田村慎也, 山田悠人, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 1 ) page: ROMBUNNO.18aK‐PS‐18   2017.3

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  49. 励起子絶縁体候補物質Ta<sub>2</sub>NiSe<sub>5</sub>の放射光X線非弾性散乱

    中埜彰俊, 田村慎也, 片山尚幸, 筒井智嗣, 松石聡, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 1 ) page: ROMBUNNO.17aL21‐10   2017.3

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  50. 三角格子をもつ混合原子価鉄酸化物β‐NaFe<sub>2</sub>O<sub>3</sub>の電荷・磁気秩序

    小林慎太郎, 澤博, 道岡千城, 植田浩明, 吉村一良

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 1 ) page: ROMBUNNO.19pL22‐12   2017.3

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  51. スピン1/2ハニカム格子反強磁性体Cu<sub>2</sub>(pymca)<sub>3</sub>(ClO<sub>4</sub>)の強磁場磁化過程

    奥谷顕, 木田孝則, 鳴海康雄, 下川統久朗, 菅原健人, 片山尚幸, 澤博, 本多善太郎, 萩原政幸

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 1 ) page: ROMBUNNO.17pC36‐9 - 1077   2017.3

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    DOI: 10.11316/jpsgaiyo.72.1.0_1077

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  52. 放射光単結晶X線回折によるβパイロクロア型CsW<sub>2</sub>O<sub>6</sub>の構造物性研究

    天野春樹, 二木健太, 岡本佳比古, 竹中康司, 片山尚幸, 澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 1 ) page: ROMBUNNO.19pL22‐7   2017.3

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  53. 構造物性からみた金属絶縁体転移と格子変形

    澤博

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 1 ) page: ROMBUNNO.17pK31‐3   2017.3

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  54. 時間分解光電子分光による励起子絶縁体Ta<sub>2</sub>NiSe<sub>5</sub>における光誘起金属相の観測

    小川優, 鈴木剛, 山本貴士, 岡田大, 染谷隆史, 道前翔矢, 渡邊真莉, 片山尚幸, 野原実, 高木英典, 高木英典, LU Y.F, 澤博, 溝川貴司, 藤澤正美, 金井輝人, 石井順久, 板谷治郎, 辛埴, 岡崎浩三

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 1 ) page: ROMBUNNO.17aL21‐11   2017.3

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  55. ポンプ-プローブ分光によるTa<sub>2</sub>NiSe<sub>5</sub>の励起子絶縁体相融解ダイナミクスの研究

    水井誠, 宮本辰也, 平田純也, 山川大路, 貴田徳明, 中埜彰俊, 澤博, 岡本博, 岡本博

    日本物理学会講演概要集(CD-ROM)   Vol. 72 ( 2 )   2017

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Presentations 65

  1. 価電子密度解析と超精密構造解析の現状と将来 Invited

    澤 博

    第36回日本放射光学会年会・放射光科学合同シンポジウム  2023.1.8  日本放射光学会

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    Event date: 2023.1

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

    Venue:立命館大学  

  2. 放射光X線回折を用いた価電子密度解析 Invited

    澤 博

    第30回有機結晶シンポジウム  2022.11.4  公益社団法人 日本化学会 有機結晶部会

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    Event date: 2022.11

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

    Venue:名古屋大学 野依記念学術交流館  

  3. 精密電子密度解析による価電子密度の直接観測 Invited

    澤博

    第34回日本放射光学会年会・ 放射光科学合同シンポジウム  2020.1.9  日本放射光学会

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    Event date: 2021.1

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

    Venue:ウインクあいち(愛知県産業労働センター)  

  4. 放射光X線回折による分子のフロンティア軌道の研究 Invited

    澤博

    第13回分子科学討論会  2019.11.18  分子科学会

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    Event date: 2019.9

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

    Venue:名古屋大学 東山キャンパス  

  5. Direct Observation of the Molecular Orbital Distribution by Synchrotron X-ray Diffraction Invited International conference

    Hiroshi Sawa

    International Conference on Coordination Chemistry, 2018  2018.8.1 

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    Event date: 2018.7 - 2018.8

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

  6. 放射光X線精密構造解析によるTi酸化物の軌道秩序の直接観測

    澤博,岡林弘卓,西堀英治,田口康二郎A,有馬孝尚A,B,十倉好紀A,C

    日本物理学会第65回年次大会 

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    Event date: 2010.3

    Language:Japanese  

    Country:Japan  

  7. X線精密構造解析による(DBr-DCNQI)2Cuの電子状態の研究

    日本物理学会第65回年次大会 

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    Event date: 2010.3

    Language:Japanese  

    Country:Japan  

  8. パイロクロア酸化物Pr2Ir2O7におけるPrとIrの組成比変化および元素置換に伴う構造変化

    西堀英治,熊代哲也,真木祥千子,澤博,大田健雄A,町田洋A,中辻知A

    日本物理学会第65回年次大会 

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    Event date: 2010.3

    Language:Japanese  

    Country:Japan  

  9. 放射光単結晶X線で見たクラスレート化合物Ba8Ga16Sn30とBa8Ga16Ge30のカゴ構造のn型p型の差

    酒井理宇,澤博,西堀英治,青柳忍,高畠敏朗A,末國晃一郎A,M.A. AvilaA

    日本物理学会第65回年次大会 

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    Event date: 2010.3

    Language:Japanese  

  10. ナノ空間を有する[RuⅡ(Hbim)3]Co(Cp)2の構造

    熊代哲也、西堀英治、澤博、田所誠

    第23回日本放射光学会年会 放射光科学合同シンポジウム 

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    Event date: 2010.1

    Language:Japanese  

    Country:Japan  

  11. 放射光X線回折を用いた分子性導体(DBr-DCNQI)3Cuの電子密度解析

    真木祥千子、西堀英治、岡林弘卓、佐藤亮太、青柳忍、澤博、加藤礼三

    第23回日本放射光学会年会 放射光科学合同シンポジウム 

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    Event date: 2010.1

    Language:Japanese  

  12. BL02B1大型湾曲IPカメラを用いた単結晶高分解能電子密度分布解析の現状

    青柳忍、西堀英治、杉本邦久、大隈寛幸、高田昌樹、澤博

    第23回日本放射光学会年会 放射光科学合同シンポジウム 

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    Event date: 2010.1

    Language:Japanese  

    Country:Japan  

  13. GPUを用いた文末未知構造高速決定システム

    西堀英治、澤博、坂田誠

    第23回日本放射光学会年会 放射光科学合同シンポジウム 

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    Event date: 2010.1

    Language:Japanese  

    Country:Japan  

  14. 2 次元検出器を用いた単結晶X線精密構造解析のための測定及び強度積分のアルゴリズムの開発

    日本結晶学会2009年年会 

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    Event date: 2009.12

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  15. SPring-8 放射光X 線IP カメラによる軌道電子可視化の試み

    日本結晶学会2009年年会 

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    Event date: 2009.12

    Language:Japanese   Presentation type:Poster presentation  

  16. Challenge to Atomic Orbital Visualization by 0.2A Resolution Synchrotron Radiation Single Crystal Experiment International conference

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    Event date: 2009.10

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

  17. 配列ナノ空間物質の結晶構造

    第13回Spring-8シンポジウム 

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    Event date: 2009.9

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

    単結晶高分解能電子密度分布解析による精密構造物性研究

  18. SPring-8における構造物性研究の新たな方向性

    第13回Spring-8シンポジウム 

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    Event date: 2009.9

    Language:Japanese  

    Country:Japan  

  19. 内包C60の精密構造解析

    第37回フラーレン・ナノチューブ総合シンポジウム 

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    Event date: 2009.9

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

    Country:Japan  

  20. α-(ET)2I3の常圧下での構造解析による電荷不均化の観測

    京都大学基礎物理学研究所 

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    Event date: 2009.7

    Language:Japanese  

    Country:Japan  

  21. KMnF3の高圧下電子密度分布解析

    青栁忍、西堀英治、大石泰生、黒岩芳弘、澤博、高田昌樹、坂田誠

    日本物理学会 2009第64回年次大会 

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    Event date: 2009.3

    Language:Japanese  

    Country:Japan  

  22. 放射光精密電子密度解析による遷移金属酸化物の軌道秩序の直接観測

    栗田明宏、西堀英治、澤博

    日本物理学会 2009第64回年次大会 

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    Event date: 2009.3

    Language:Japanese  

    Country:Japan  

  23. KMnF3の高圧下電子密度分布解析

    青栁忍、西堀英治、大石泰生、黒岩芳弘、澤博、高田昌樹、坂田誠

    日本物理学会 2009第64回年次大会 

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    Event date: 2009.3

    Language:Japanese  

    Country:Japan  

  24. 放射光精密電子密度解析による遷移金属酸化物の軌道秩序の直接観測

    栗田明宏、西堀英治、澤博

    日本物理学会 2009第64回年次大会 

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    Event date: 2009.3

    Language:Japanese  

    Country:Japan  

  25. 放射光X線を用いた単結晶MEM解析による分子性物質系の分子軌道の直接観測

    第26回PFシンポジウム 

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    Event date: 2009.3

    Language:Japanese  

    Country:Japan  

  26. Spring-8の放射光を用いた高分解能X線回折データによる電子密度分布解析

    栗田明宏、西堀英治、青栁忍、澤博

    第22回日本放射光学会年会 放射光科学合同シンポジウム 

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    Event date: 2009.1

    Language:Japanese  

    Country:Japan  

  27. 放射光粉末X線回折によるSn欠損type-ⅠクラスレートCs8Sn44☐2の結晶構造の解析

    第3回特定領域会議 

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    Event date: 2009.1

    Language:Japanese  

    Country:Japan  

  28. 高分解能粉末X線回折データを用いた電子密度分布解析

    西堀英治、青栁忍、澤博

    第4回粉末回折法討論会 

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    Event date: 2008.12

    Language:Japanese  

    Country:Japan  

  29. Wigner Crystallization in a Molecular Conductor, (DI-DCNQI)2Ag International conference

    The International Symposium on Anomalous Quantum Materials 2008 and the 7-th Asia-Pacific Workshop 

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    Event date: 2008.11

    Language:English  

    Country:Japan  

  30. The Role of Precise Structure Analysis for Molecular Crystal System International conference

    Institute of Materials Structure Science-Symposium 

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    Event date: 2008.10

    Language:English  

    Country:Japan  

  31. 放射光単結晶X線回折による内包フラーレンの観測

    産学官・金属内包フラーレン/フラーレン・フォーラム2008 

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    Event date: 2008.10

    Language:Japanese  

  32. 放射光を用いたCoSb3スクッテルダイトの精密電子密度分布解析

    大野敦子、佐々木聡、西堀英治、青栁忍、、坂田誠、BoBrummerstedt Iversen、澤博

    日本物理学会2008秋季大会 

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    Event date: 2008.9

    Language:Japanese  

  33. 放射光粉末X線回折によるSn欠損type-ⅠクラスレートCs8Sn44☐2の結晶構造の解析

    土屋達生、西堀英治、澤博、BoB.Iversen

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    Event date: 2008.9

    Language:Japanese  

    Country:Japan  

  34. Geometrical Frustration and Charge Ordering of Molecular Conductor International conference

    The 21st IUCr Satellite Meeting 

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    Event date: 2008.8

    Language:English  

    Country:Japan  

  35. Charge ordering state of molecular conductoe detected by synchrotron dadiation x-ray diffraction International conference

    International Symposium on Molecular Conductors 2008 

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    Event date: 2008.7

    Language:English  

  36. 配列ナノ空間物質の結晶構造

    第2回領域会議 

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    Event date: 2008.6

    Language:Japanese  

    Country:Japan  

  37. キラル磁性体[Mn(HL)(H2O)][Mn(CN)6]・2H2Oの熱容量

    安塚周磨、山村泰久、隅田真人、齋藤一弥、兼子和佳子、大場正昭、北川進、澤博

    日本化学会2008 第88回春季年会 

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    Event date: 2008.3

    Language:Japanese  

    Country:Japan  

  38. Pr0.55(Ca1-ySry)0.45MnO3薄膜の光スイッチング効果-構造の光照射効果

    若林裕助、小川直毅、田久保直子、市川広彦、佐藤篤志、一柳光平、足立伸一、腰原伸也、宮野健次郎、澤博

    日本物理学会2008 第63回年次大会 

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    Event date: 2008.3

    Language:Japanese  

    Country:Japan  

  39. 放射光による単結晶H2@C60の精密構造解析

    土岐睦、澤博、村田靖次郎、小松紘一、二川秀史、赤阪健、谷垣勝巳

    日本物理学会2008 第63回年次大会 

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    Event date: 2008.3

    Language:Japanese  

    Country:Japan  

  40. ナノ孔を有する一次元積層型発光性白金錯体の圧力応答

    小林厚志、米村翼、加藤昌子、若林裕助、澤博

    日本化学会2008 第88回春季年会 

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    Event date: 2008.3

    Language:Japanese  

    Country:Japan  

  41. 放射光による単結晶C60の精密構造解析

    土岐睦、澤博、村田靖次郎

    日本放射光学会2008 

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    Event date: 2008.1

    Language:Japanese  

    Country:Japan  

  42. Wigner Crystallization in a Molecular Conductor, (DI-DCNQI)2Ag International conference

    Asian Crystallographic Association 

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    Event date: 2007.11

    Language:English  

  43. 電荷移動相転移を示す鉄混合原子価錯体の低温構造

    真木祥千子、市川広彦、足立伸一、澤博、腰原伸也、木田紀行、榎本真哉、小島憲道

    日本物理学会2007 第62回年次大会 

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    Event date: 2007.9

    Language:Japanese  

    Country:Japan  

  44. 光誘起金属-絶縁体スイッチング可能なPr0.55(Ca1-ySry)0.45MnO3薄膜の構造と物性

    若林裕助、澤博、田久保直子、宮野健次郎

    日本物理学会2007 第62回年次大会 

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    Event date: 2007.9

    Language:Japanese  

    Country:Japan  

  45. 放射光による単結晶C60の精密構造解析

    澤博、土岐睦、村田靖次朗

    日本物理学会2007 第62回年次大会 

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    Event date: 2007.9

    Language:Japanese  

    Country:Japan  

  46. (Pb,Sr)TiO3ナノパウダーの構造解析

    鹿内文仁、狩野旬、張帆、唐木智明、安達正利、澤博、小島誠治、池田進、神山崇

    日本物理学会2007 第62回年次大会 

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    Event date: 2007.9

    Language:Japanese  

    Country:Japan  

  47. 放射光X線回折によるガス内包フラーレンの構造物性研究

    垣内徹、土岐睦、赤田美佐保、澤博、谷垣勝己、八木ヶ谷謙一、高木英典、Nita Dragoe、村田理尚、村田靖次郎、小松紘一

    日本物理学会2007 春季大会 

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    Event date: 2007.3

    Language:Japanese  

    Country:Japan  

  48. KCuxZn1-xF3における不純物Znまわりの局所構造の観測

    多々見央、安藤悠也、村上洋一、岩佐和晃、中尾裕則、吉良弘、新岡真也、澤博、若林裕助、伊藤晋一、垣内徹

    日本物理学会2007 春季大会 

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    Event date: 2007.3

    Language:Japanese  

    Country:Japan  

  49. 放射光回折の有機導体への応用:分子の電荷分布を見る

    澤博

    日本物理学会2007 春季大会 

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    Event date: 2007.3

    Language:Japanese  

    Country:Japan  

  50. 放射光を用いた単結晶TTF-CA の電子密度解析2

    富田文菜、佐藤篤志、M. Chollet、田崎遼子、足立伸一、野澤俊介、一柳光平、大門正博、河田洋、澤博、L.Guerin、E.Collet、P.Rabiller、腰原伸也

    日本物理学会2007 春季大会 

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    Event date: 2007.3

    Language:Japanese  

    Country:Japan  

  51. 銀を含む化合物Ag2NiO2 の低温構造解析と新規銀化合物の探索2

    吉田紘行、村岡祐治、広井善二、垣内徹、澤博、Christian Oberndorfer、Martin Jansen

    日本物理学会2007 春季大会 

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    Event date: 2007.3

    Language:Japanese  

    Country:Japan  

  52. PF 新構造物性ビームライン短周期アンジュレータBL-3A 建設の現状

    若林裕助、澤博、岩住俊明、平野馨一、河田洋、森丈晴、大田浩正

    日本放射光学会2007 

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    Event date: 2007.1

    Language:Japanese  

    Country:Japan  

  53. Low-dimensionally Ordered Structure in Metal Complexes Analyzed with the Energy Spectrum of the Diffuse X-ray Scattering Intensity

    The 1st Workshop of the Asia/ Oceania Forum for Synchrotron Radiation Research 

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    Event date: 2006.11

    Language:English  

  54. 有機超伝導体κL-(DMEDO-TSeF)2[Au(CN)4](THF)における構造相転移

    川本正、森健彦、垣内徹、澤博、白旗崇、木舩愛、吉野浩子、今久保達郎

    日本物理学会2006、秋季大会 

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    Event date: 2006.9

    Language:Japanese  

    Country:Japan  

  55. 放射光を用いた単結晶TTF-CA の精密構造解析と電子密度解析

    富田文菜、佐藤篤志、M.Chollet、田崎遼子、足立伸一、一柳光平、野澤俊介、大門正博、河田洋、澤博、L.Guerin、E.Collet、P.Rabiller、腰原伸也

    日本物理学会2006、秋季大会 

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    Event date: 2006.9

    Language:Japanese  

    Country:Japan  

  56. MX-Ladder 錯体における構造制御と電子状態の研究

    小林厚志、大坪主弥、北川宏、若林裕助、澤博

    日本物理学会2006、秋季大会 

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    Event date: 2006.9

    Language:Japanese  

    Country:Japan  

  57. 放射光を用いたH2@C60 の精密構造解析

    赤田美佐保、垣内徹、村田靖次郎、小松紘一、谷垣勝己、若林裕助、澤博

    日本物理学会2006、秋季大会 

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    Event date: 2006.9

    Language:Japanese  

    Country:Japan  

  58. 銀を含む化合物Ag2NiO2 の低温構造解析と新規銀化合物の探索

    吉田紘行、村岡祐治、広井善二、Timo Soergel、Martin Jansen、垣内徹、澤博

    日本物理学会2006、秋季大会 

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    Event date: 2006.9

    Language:English  

    Country:Japan  

  59. バナジウムブロンズβ-Sr0.33V2O5 における悪魔の階段

    植田浩明、山内徹、大和田謙二、佐賀山基、澤博、上田寛

    日本物理学会2006、秋季大会 

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    Event date: 2006.9

    Language:Japanese  

    Country:Japan  

  60. SrTiO3(011)基板に作成したNd0.5Sr0.5MnO3 薄膜中の軌道秩序の磁場応答

    若林裕助、佐賀山基、有馬孝尚、備前大輔、中尾裕則、村上洋一、中村優男、荻本泰史、宮野健次郎、澤博

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    Event date: 2006.9

    Language:Japanese  

    Country:Japan  

  61. (011)基板ハーフドープMn 酸化物薄膜の軌道秩序状態

    若林裕助、備前大輔、中尾裕則、村上洋一、中村優男、荻本泰史、宮野健次郎、澤博

    日本物理学会2006、秋季大会 

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    Event date: 2006.9

    Language:Japanese  

  62. Structural Study of MgB2-type Superconductor CaAlSi using SR X-ray and TOF-Neutron Diffraction Methods

    The 1st International Symposium of Quantum Beam Science directorate of JAEA 

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    Event date: 2006.8

    Language:English  

  63. Structural Study of MgB2-type Superconductor Ca(Al1/2Si1/2)2

    The International Symposium on Anomalous Quantum Materials 2006 and the 5th Asia-Pacific Workshop 

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    Event date: 2006.6

    Language:English  

  64. Direct Observation of a Gas Molecule (H2, Ar) Swallowed by C60

    The Ninth International Conference on Synchrotron Radiation Instrumentation 

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    Event date: 2006.5

    Language:English  

  65. Orbital Ordered Structure of a Manganite Thin Film Observed by K-edge Resonant X-ray Scattering International conference

    The Ninth International Conference on Synchrotron Radiation Instrumentation 

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    Event date: 2006.5

    Language:English  

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Works 11

  1. 乱れに強い新しい量子液体状態の発見

    2012.5

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    20120504掲載

  2. 金属フラーレン大量合成に成功名大Gなど研究 産業への応用に期待

    2010.6

  3. LITHIUM CATION ISOLATED WITHIN FULLERENE

    2010.6

  4. 新しいナノテク素材を開発

    2010.6

  5. 理研ら、Li@C60フラーレンの大量合成と単結晶構造決定に成功

    2010.6

  6. 金属イオン内包フラーレン単結晶構造を決定名大など 大量合成法も開発

    2010.6

  7. 球状炭素分子の内部にリチウム名古屋大など合成太陽電池に応用

    2010.6

  8. 名大 菱化システムと連携X線構造解析法を製品化

    2010.4

  9. 微粉末結晶構造最短10分でCG解析名大など、新薬開発に応用

    2010.4

  10. 高エネルギー加速器研究機構一般公開に向けて

    2007.9

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    高エネルギー加速器研究機構一般公開に向けての紹介記事

  11. 放射光がもたらした成果物性科学の魅力を紹介講演「”もの”の不思議を探る」

    2007.8

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Research Project for Joint Research, Competitive Funding, etc. 3

  1. 放射光X線散乱測定による強相関電子系物質の軌道自由度の解明

    Grant number:21-1055  2021.10 - 2023.3

    公益財団法人 山田科学振興財団  財団からの研究助成  研究援助

    澤博

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    Grant type:Competitive

    Grant amount:\3400000 ( Direct Cost: \3400000 )

  2. 新規蛍光体の結晶構造

    2015.4

    企業からの受託研究 

  3. 高プロトン伝導性酸化物材料の構造研究

    2015.4 - 2017.3

    学内共同研究 

KAKENHI (Grants-in-Aid for Scientific Research) 8

  1. 放射光X線回折による軌道自由度の直接観測を応用した磁性材料の電子状態の解明

    Grant number:23K23202  2024.2 - 2027.3

    科学研究費助成事業  基盤研究(B)

    澤 博

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    Authorship:Principal investigator 

    Grant amount:\7930000 ( Direct Cost: \6100000 、 Indirect Cost:\1830000 )

  2. Electronic state of magnetic materials by applying direct observation of orbital degrees of freedom by synchrotron radiation X-ray diffraction

    Grant number:22H01934  2022.4 - 2027.3

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

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    Authorship:Principal investigator 

    Grant amount:\17160000 ( Direct Cost: \13200000 、 Indirect Cost:\3960000 )

  3. 分子軌道設計による新規電子相の開拓 研究課題番号20110003

    2008.4 - 2014.3

    科学研究費補助金  新学術領域研究(研究領域提案型)

    小林昭子

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    Authorship:Coinvestigator(s) 

  4. 放射光X線による強相関電子系物質の電荷密度解析システムの構築

    2008.4 - 2011.3

    科学研究費補助金  基盤研究(A),課題番号:20244059

    澤 博

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    Authorship:Principal investigator 

  5. 配列ナノ空間物質の結晶構造

    2007.5 - 2012.3

    科学研究費補助金  特定領域研究・19051015

    澤博

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    Authorship:Principal investigator 

    領域代表者:谷垣勝己

  6. 放射光X線回折による分子軌道の電子密度分布の直接観測

    2006.5 - 2008.3

    科学研究費補助金  基盤研究(B)・18310073

    澤博

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    Authorship:Principal investigator 

  7. 放射光単結晶解析によるフラーレンケージに閉じ込められたガス分子の直接観測

    2006 - 2007.3

    科学研究費補助金  特定領域研究・公募研究・18033060

    澤博

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    Authorship:Principal investigator 

  8. 異常量子物質の創製~新しい物理を生む新物質~

    2004 - 2009.3

    科学研究費補助金  特定領域研究・16076202

    澤博

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    Authorship:Coinvestigator(s) 

    計画班 班長:村上洋一

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Teaching Experience (On-campus) 4

  1. 物性物理学第1

    2022

     詳細を見る

    物質の性質、機能を解明する物性物理学では主に結晶性の物質を扱う。そこで本講義では物性物理学を本格的に学習する最初の段階として結晶の対称性と結晶構造の求め方を学習する。結晶という周期構造と逆空間の関係、フーリエ変換の適用によって結晶によるX線回折が体系化できることを学ぶ。これらの基本的な結晶学の知識が、物性研究、材料開発に必要な応用力となる。

  2. 構造物性工学特論

    2022

     詳細を見る

    本講義では先端的なプローブとして量子ビームを用いた構造物性研究の応用力を身に付けることを目標とする。物性の理解には様々な外場応答を調べる必要があり、最近の実験的研究は極限までその性能を高めた最先端プローブを用いて新しい物性物理学を切り拓くことを目指している。この特異で極めて興味深い物性を理解するためには、データの解析方法の基本原理を習得し,電子密度の決定によって電子状態を明らかにする必要がある。このために必要な群論、結晶化学と共に未知物質の開発のための基本的な知識を学ぶ。

  3. 基礎セミナー

    2022

     詳細を見る

    本授業科目は,初年次生を大学教育へ導入し,自立した学習能力を身につけるとともに,文・理に共通した基礎的学力や技能を養うために,多面的な知的トレーニングによって,コモンベーシックとしての読み,書き,話す能力の涵養を図るとともに,真理探究の方法と面白さを学ぶことが目的である。

  4. Foundations of Electromagnetics II

    2011