Updated on 2024/10/11

写真a

 
YAMAKAWA Youichi
 
Organization
Graduate School of Science Lecturer
Graduate School
Graduate School of Science
Undergraduate School
School of Science Department of Physics
Title
Lecturer
External link

Degree 1

  1. 博士(理学) ( 2010.3   新潟大学 ) 

Research Interests 4

  1. ネマティック転移

  2. 軌道自由度

  3. 超伝導

  4. 強相関電子系

Research Areas 1

  1. Natural Science / Magnetism, superconductivity and strongly correlated systems  / 電子相関 超伝導 多軌道 ネマティック

Research History 4

  1. Nagoya University   Lecturer

    2021.3

  2. Nagoya University   Assistant Professor

    2016.4 - 2021.3

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    Country:Japan

  3. Nagoya University   Designated assistant professor

    2014.12 - 2016.3

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    Country:Japan

  4. Nagoya University   Researcher

    2011.4 - 2014.11

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    Country:Japan

Education 3

  1. Niigata University   Graduate School, Division of Science and Technology

    2007.4 - 2010.3

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    Country: Japan

  2. Niigata University   Graduate School, Division of Science and Technology

    2005.4 - 2007.3

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    Country: Japan

  3. Niigata University   Faculty of Science

    2001.4 - 2005.3

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    Country: Japan

Professional Memberships 1

  1. The Physical Society of Japan

Committee Memberships 2

  1. 日本物理学会   領域8 運営委員  

    2018.4 - 2019.3   

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    磁性
    2018/10~2019/3: 領域運営委員副代表

  2. 日本物理学会   領域10 運営委員  

    2012.4 - 2013.3   

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    フォノン分科

Awards 1

  1. 第24回(2019年)論文賞授賞論文

    2019.3   日本物理学会   Line-Node Dirac Semimetal and Topological Insulating Phase in Noncentrosymmetric Pnictides CaAgX (X = P, As)

    Ai Yamakage, Youichi Yamakawa, Yukio Tanaka, and Yoshihiko Okamoto

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

 

Papers 76

  1. Drastic magnetic-field-induced chiral current order and emergent current-bond-field interplay in kagome metals Reviewed International journal

    Rina Tazai, Youichi Yamakawa, Hiroshi Kontani

    Proceedings of the National Academy of Sciences USA   Vol. 121 ( 3 ) page: e2303476121-1 - e2303476121-10   2024.1

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Proceedings of the National Academy of Sciences  

    In kagome metals, the chiral current order parameter
    η with time-reversal-symmetry-breaking is the source of various exotic electronic states, while the method of controlling the current order and its interplay with the star-of-David bond order ϕ are still unsolved. Here, we reveal that tiny uniform orbital magnetization Morb[η,ϕ] is induced by the chiral current order, and its magnitude is prominently enlarged under the presence of the bond order. Importantly, we derive the magnetic-field (hz)-induced Ginzburg–Landau (GL) free energy expression ΔF[hz,η,ϕ]∝−hzMorb[η,ϕ], which enables us to elucidate the field-induced current-bond phase transitions in kagome metals. The emergent current-bond-
    hz trilinear coupling term in the free energy, −m1hzη·ϕ, naturally explains the characteristic magnetic-field sensitive electronic states in kagome metals, such as the field-induced current order and the strong interplay between the bond and current orders. The GL coefficients of ΔF[hz,η,ϕ] derived from the realistic multiorbital model are appropriate to explain various experiments. Furthermore, we discuss the field-induced loop current orders in the square lattice models that have been studied in cuprate superconductors.

    DOI: 10.1073/pnas.2303476121

  2. Charge-loop current order and Z3 nematicity mediated by bond order fluctuations in kagome metals Reviewed International journal

    Rina Tazai, Youichi Yamakawa, Hiroshi Kontani

    Nature Communications   Vol. 14   page: 7845-1 - 7845-9   2023.11

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

    Recent experiments on geometrically frustrated kagome metal AV3Sb5 (A = K, Rb, Cs) have revealed the emergence of the charge loop current (cLC) order near the bond order (BO) phase. However, the origin of the cLC and its interplay with other phases have been uncovered. Here, we propose a novel mechanism of the cLC state, by focusing on the BO phase common in kagome metals. The BO fluctuations in kagome metals, which emerges due to the Coulomb interaction and the electron-phonon coupling, mediate the odd-parity particle-hole condensation that gives rise to the topological current order. Furthermore, the predicted cLC+BO phase gives rise to the Z3-nematic state in addition to the giant anomalous Hall effect. The present theory predicts the close relationship between the cLC, the BO, and the nematicity, which is significant to understand the cascade of quantum electron states in kagome metals. The present scenario provides a natural understanding.

    DOI: 10.1038/s41467-023-42952-6

  3. Mechanism of exotic density-wave and beyond-Migdal unconventional superconductivity in kagome metal AV(3)Sb(5) (A = K, Rb, Cs) Reviewed International journal

    Tazai Rina, Yamakawa Youichi, Onari Seiichiro, Kontani Hiroshi

    SCIENCE ADVANCES   Vol. 8 ( 13 ) page: eabl4108-1 - eabl4108-9   2022.4

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

    DOI: 10.1126/sciadv.abl4108

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  4. Odd-parity spin-loop-current order mediated by transverse spin fluctuations in cuprates and related electron systems Reviewed International journal

    H. Kontani, Y. Yamakawa, R. Tazai, and S. Onari

    Physical Review Research   Vol. 3 ( 1 ) page: 013127-1 - 013127-13   2021.2

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

    Unconventional symmetry-breaking phenomena due to nontrivial order parameters attract increasing attention in strongly correlated electron systems. Here, we predict theoretically the occurrence of nanoscale spontaneous spin current, called the spin-loop-current (sLC) order, as a promising origin of the pseudogap and electronic nematicity in cuprates. We reveal that the sLC is driven by the odd-parity electron-hole condensations that are mediated by transverse spin fluctuations around the pseudogap temperature T∗. At the same temperature, odd-parity magnon pair condensation occurs. The sLC order is “hidden” in that neither internal magnetic field nor charge-density modulation is induced, whereas the predicted sLC with finite wave-number naturally gives the Fermi arc structure. In addition, the fluctuations of sLC order work as attractive pairing interaction between adjacent hot spots, which enlarges the d-wave superconducting transition temperature Tc. The sLC state will be a key ingredient in understanding the pseudogap, electronic nematicity, as well as superconductivity in cuprates and other strongly correlated metals.

    DOI: 10.1103/PhysRevResearch.3.013127

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  5. Nematicity and Magnetism in FeSe and Other Families of Fe-Based Superconductors Reviewed International journal

    Yamakawa Youichi, Onari Seiichiro, Kontani Hiroshi

    PHYSICAL REVIEW X   Vol. 6 ( 2 ) page: 021032-1 - 021032-15   2016.6

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

    Nematicity and magnetism are two key features in Fe-based superconductors, and their interplay is one of the most important unsolved problems. In FeSe, the magnetic order is absent below the structural transition temperature Tstr=90 K, in stark contrast to the fact that the magnetism emerges slightly below Tstr in other families. To understand such amazing material dependence, we investigate the spin-fluctuation-mediated orbital order (nxz≠nyz) by focusing on the orbital-spin interplay driven by the strong-coupling effect, called the vertex correction. This orbital-spin interplay is very strong in FeSe because of the small ratio between the Hund’s and Coulomb interactions (J¯/U¯) and large dxz, dyz-orbital weight at the Fermi level. For this reason, in the FeSe model, the orbital order is established irrespective of the fact that the spin fluctuations are very weak, so the magnetism is absent below Tstr. In contrast, in the LaFeAsO model, the magnetic order appears just below Tstr both experimentally and theoretically. Thus, the orbital-spin interplay due to the vertex correction is the key ingredient in understanding the rich phase diagram with nematicity and magnetism in Fe-based superconductors in a unified way.

    DOI: 10.1103/PhysRevX.6.021032

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  6. Sign-Reversing Orbital Polarization in the Nematic Phase of FeSe due to the C-2 Symmetry Breaking in the Self-Energy Reviewed

    Onari Seiichiro, Yamakawa Youichi, Kontani Hiroshi

    PHYSICAL REVIEW LETTERS   Vol. 116 ( 22 ) page: 227001-1 - 227001-6   2016.6

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

    DOI: 10.1103/PhysRevLett.116.227001

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  7. Real-Space Loop Current Pattern in Time-Reversal-Symmetry Breaking Phase in Kagome Metals Reviewed

    Shimura, K; Tazai, R; Yamakawa, Y; Onari, S; Kontani, H

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 93 ( 3 ) page: 033704-1 - 033704-5   2024.3

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

    DOI: 10.7566/JPSJ.93.033704

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  8. Superconductivity in Ternary Zirconium Telluride Zr6MTe2 with 3d Transition Metals Reviewed

    Matsumoto, H; Yamakawa, Y; Okuma, R; Nishio-Hamane, D; Okamoto, Y

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 93 ( 2 ) page: 023705-1 - 023705-5   2024.2

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

    DOI: 10.7566/JPSJ.93.023705

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  9. Superconductivity in Ternary Germanide ScPdGe and Silicide ScPdSi Reviewed

    Shinoda, Y; Okamoto, Y; Yamakawa, Y; Takatsu, H; Kageyama, H; Hirai, D; Takenaka, K

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 93 ( 2 ) page: 023701-1 - 023701-4   2024.2

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

    DOI: 10.7566/JPSJ.93.023701

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  10. Low temperature phase transitions inside the CDW phase in the kagome metals AV3Sb5 (A=Cs, Rb, K): Significance of mixed-type Fermi surface electron correlations Reviewed

    Jianxin Huang, Rian Tazai, Youichi Yamakawa, Seiichiro Onari, and Hiroshi Kontani

    Physical Review B   Vol. 109 ( 4 ) page: L041110-1 - L041110-6   2024.1

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

    DOI: 10.1103/PhysRevB.109.L041110

  11. Superconductivity in Ternary Scandium Telluride Sc6MTe2 with 3d, 4d, and 5d Transition Metals Reviewed

    Shinoda, Y; Okamoto, Y; Yamakawa, Y; Matsumoto, H; Hirai, D; Takenaka, K

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 92 ( 10 ) page: 103701-1 - 103701-5   2023.8

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

    DOI: 10.7566/JPSJ.92.103701

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  12. Rigorous formalism for unconventional symmetry breaking in Fermi liquid theory and its application to nematicity in FeSe

    Tazai Rina, Matsubara Shun, Yamakawa Youichi, Onari Seiichiro, Kontani Hiroshi

    PHYSICAL REVIEW B   Vol. 107 ( 3 )   2023.1

  13. Correlation-driven electronic nematicity in the Dirac semimetal BaNiS2 Reviewed

    C. J. Butler, Y. Kohsaka, Y. Yamakawa, M. S. Bahramy, S. Onari, H. Kontani, T. Hanaguri, and S. Shamoto

    Proceedings of the National Academy of Sciences   Vol. 119 ( 49 ) page: e2212730119-1 - e2212730119-8   2022.12

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

    DOI: 10.1073/pnas.2212730119

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  14. d- and p-wave Quantum Liquid Crystal Orders in Cuprate Superconductors, Kappa-(BEDT-TTF)(2)X, and Coupled Chain Hubbard Models: Functional-renormalization-group Analysis

    Tazai Rina, Yamakawa Youichi, Tsuchiizu Masahisa, Kontani Hiroshi

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 90 ( 11 )   2021.11

  15. Unconventional orbital charge density wave mechanism in the transition metal dichalcogenide 1T-TaS2 Reviewed

    Hirata Toru, Yamakawa Youichi, Onari Seiichiro, Kontani Hiroshi

    Physical Review Research   Vol. 3 ( 3 ) page: L032053-1 - L032053-6   2021.8

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

    DOI: 10.1103/PhysRevResearch.3.L032053

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  16. Pressure-induced reconstitution of Fermi surfaces and spin fluctuations in S-substituted FeSe

    Kuwayama T., Matsuura K., Gouchi J., Yamakawa Y., Mizukami Y., Kasahara S., Matsuda Y., Shibauchi T., Kontani H., Uwatoko Y., Fujiwara N.

    SCIENTIFIC REPORTS   Vol. 11 ( 1 )   2021.8

  17. Unconventional Density Waves and Superconductivities in Fe-Based Superconductors and Other Strongly Correlated Electron Systems Invited Reviewed

    H. Kontani, R. Tazai, Y. Yamakawa, and S. Onari

    Advances in Physics   Vol. 70 ( 3 ) page: 355 - 443   2021.7

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

    DOI: 10.1080/00018732.2022.2144590

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  18. Development of Spin Fluctuations under the Presence of d-wave Bond Order in Cuprate Superconductors Reviewed

    Ando Satoshi, Yamakawa Youichi, Onari Seiichiro, Kontani Hiroshi

    Journal of the Physical Society of Japan   Vol. 90 ( 6 ) page: 063704-1 - 063704-5   2021.6

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

    DOI: 10.7566/JPSJ.90.063704

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  19. Superconductivity in Nb2Pd3Te5 and Chemically-Doped Ta2Pd3Te5 Reviewed

    Higashihara Naoya, Okamoto Yoshihiko, Yoshikawa Yuma, Yamakawa Youichi, Takatsu Hiroshi, Kageyama Hiroshi, Takenaka Koshi

    Journal of the Physical Society of Japan   Vol. 90 ( 6 ) page: 063705-1 - 063705-4   2021.6

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

    DOI: 10.7566/JPSJ.90.063705

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  20. Prediction of pseudogap formation due to d-wave bond-order in organic superconductor κ-(BEDT-TTF)2X Reviewed

    Tazai Rina, Yamakawa Youichi, Tsuchiizu Masahisa, Kontani Hiroshi

    Physical Review Research   Vol. 3 ( 2 ) page: L022014-1 - L022014-6   2021.5

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

    DOI: 10.1103/PhysRevResearch.3.L022014

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  21. Emergence of charge loop current in the geometrically frustrated Hubbard model: A functional renormalization group study Reviewed

    Tazai Rina, Yamakawa Youichi, Kontani Hiroshi

    PHYSICAL REVIEW B   Vol. 103 ( 16 )   2021.4

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

    DOI: 10.1103/PhysRevB.103.L161112

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  22. High-mobility carriers induced by chemical doping in the candidate nodal-line semimetal CaAgP

    Okamoto Yoshihiko, Saigusa Kazushige, Wada Taichi, Yamakawa Youichi, Yamakage Ai, Sasagawa Takao, Katayama Naoyuki, Takatsu Hiroshi, Kageyama Hiroshi, Takenaka Koshi

    PHYSICAL REVIEW B   Vol. 102 ( 11 )   2020.9

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

    DOI: 10.1103/PhysRevB.102.115101

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  23. Doping effects on electronic states in electron-doped FeSe: Impact of self-energy and vertex corrections

    Yamakawa Youichi, Onari Seiichiro, Kontani Hiroshi

    PHYSICAL REVIEW B   Vol. 102 ( 8 )   2020.8

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

    DOI: 10.1103/PhysRevB.102.081108

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  24. Superconductivity in PtSbS with a Noncentrosymmetric Cubic Crystal Structure

    Mizutani Ryosuke, Okamoto Yoshihiko, Nagaso Hayate, Yamakawa Youichi, Takatsu Hiroshi, Kageyama Hiroshi, Kittaka Shunichiro, Kono Yohei, Sakakibara Toshiro, Takenaka Koshi

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 88 ( 9 )   2019.9

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

    DOI: 10.7566/JPSJ.88.093709

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  25. Pressure-induced quantum critical point in the heavily hydrogen-doped iron-based superconductor LaFeAsO

    Takeuchi Masayoshi, Fujiwara Naoki, Kuwayama Takanori, Nakagawa Satoshi, Iimura Soshi, Matsuishi Satoru, Yamakawa Youichi, Kontani Hiroshi, Hosono Hideo

    PHYSICAL REVIEW B   Vol. 99 ( 17 )   2019.5

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

    DOI: 10.1103/PhysRevB.99.174517

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  26. Self-energy driven resonancelike inelastic neutron spectrum in the s(++)-wave state in Fe-based superconductors

    Takeuchi Lisa, Yamakawa Youichi, Kontani Hiroshi

    PHYSICAL REVIEW B   Vol. 98 ( 16 )   2018.10

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

    DOI: 10.1103/PhysRevB.98.165143

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  27. Pairing mechanism for nodal s-wave superconductivity in BaFe2(As, P)(2): Analysis beyond Migdal-Eliashberg formalism

    Nakaoka Hironori, Yamakawa Youichi, Kontani Hiroshi

    PHYSICAL REVIEW B   Vol. 98 ( 12 )   2018.9

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

    DOI: 10.1103/PhysRevB.98.125107

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  28. Edge-induced Strongly Correlated Electronic States in Two-dimensional Hubbard Model: Enhancement of Magnetic Correlations and Self-energy Effects

    Matsubara Shun, Yamakawa Youichi, Kontani Hiroshi

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 87 ( 7 )   2018.7

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

    DOI: 10.7566/JPSJ.87.073705

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  29. Large thermoelectric power factor in one-dimensional telluride Nb4SiTe4 and substituted compounds

    Okamoto Yoshihiko, Wada Taichi, Yamakawa Youichi, Inohara Takumi, Takenaka Koshi

    APPLIED PHYSICS LETTERS   Vol. 112 ( 17 )   2018.4

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

    DOI: 10.1063/1.5023427

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  30. Multistage electronic nematic transitions in cuprate superconductors: A functional-renormalization-group analysis

    Tsuchiizu Masahisa, Kawaguchi Kouki, Yamakawa Youichi, Kontani Hiroshi

    PHYSICAL REVIEW B   Vol. 97 ( 16 )   2018.4

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

    DOI: 10.1103/PhysRevB.97.165131

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  31. Abrupt change of the superconducting gap structure at the nematic critical point in FeSe1-xSx Reviewed

    Sato Yuki, Kasahara Shigeru, Taniguchi Tomoya, Xing Xiangzhuo, Kasahara Yuichi, Tokiwa Yoshifumi, Yamakawa Youichi, Kontani Hiroshi, Shibauchi Takasada, Matsuda Yuji

    PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA   Vol. 115 ( 6 ) page: 1227 - 1231   2018.2

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

    DOI: 10.1073/pnas.1717331115

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  32. Observation of Dirac-like energy band and ring-torus Fermi surface associated with the nodal line in topological insulator CaAgAs Reviewed

    Takane Daichi, Nakayama Kosuke, Souma Seigo, Wada Taichi, Okamoto Yoshihiko, Takenaka Koshi, Yamakawa Youichi, Yamakage Ai, Mitsuhashi Taichi, Horiba Koji, Kumigashira Hiroshi, Takahashi Takashi, Sato Takafumi

    NPJ QUANTUM MATERIALS   Vol. 3   2018.1

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

    DOI: 10.1038/s41535-017-0074-z

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  33. Nematicity, magnetism, and superconductivity in FeSe under pressure: Unified explanation based on the self-consistent vertex correction theory Reviewed

    Yamakawa Youichi, Kontani Hiroshi

    PHYSICAL REVIEW B   Vol. 96 ( 14 )   2017.10

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

    DOI: 10.1103/PhysRevB.96.144509

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  34. Superconductivity without a hole pocket in electron-doped FeSe: Analysis beyond the Migdal-Eliashberg formalism Reviewed

    Yamakawa Youichi, Kontani Hiroshi

    PHYSICAL REVIEW B   Vol. 96 ( 4 )   2017.7

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

    DOI: 10.1103/PhysRevB.96.045130

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  35. Plain s-Wave Superconductivity near Magnetic Criticality: Enhancement of Attractive Electron-Boson Coupling Vertex Corrections Reviewed

    Tazai Rina, Yamakawa Youichi, Tsuchiizu Masahisa, Kontani Hiroshi

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 86 ( 7 )   2017.7

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

    DOI: 10.7566/JPSJ.86.073703

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  36. Crossing-line-node semimetals: General theory and application to rare-earth trihydrides Reviewed

    Kobayashi Shingo, Yamakawa Youichi, Yamakage Ai, Inohara Takumi, Okamoto Yoshihiko, Tanaka Yukio

    PHYSICAL REVIEW B   Vol. 95 ( 24 )   2017.6

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

    DOI: 10.1103/PhysRevB.95.245208

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  37. Competing Unconventional Charge-Density-Wave States in Cuprate Superconductors: Spin-Fluctuation-Driven Mechanism Reviewed

    Kawaguchi Kouki, Yamakawa Youichi, Tsuchiizu Masahisa, Kontani Hiroshi

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 86 ( 6 )   2017.6

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

    DOI: 10.7566/JPSJ.86.063707

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  38. Large thermoelectric power factor at low temperatures in one-dimensional telluride Ta4SiTe4 Reviewed

    Inohara Takumi, Okamoto Yoshihiko, Yamakawa Youichi, Yamakage Ai, Takenaka Koshi

    APPLIED PHYSICS LETTERS   Vol. 110 ( 18 )   2017.5

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

    DOI: 10.1063/1.4982623

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  39. Unusual nodal behaviors of the superconducting gap in the iron-based superconductor $\mathrm{Ba}(\mathrm{F}{\mathrm{e}}_{0.65}\mathrm{R}{\mathrm{u}}_{0.35}{)}_{2}\mathrm{A}{\mathrm{s}}_{2}$: Effects of spin-orbit coupling Reviewed

    L. Liu, K. Okazaki, T. Yoshida, H. Suzuki, M. Horio, L. C. C. Ambolode, J. Xu, S. Ideta, M. Hashimoto, D. H. Lu, Z.-X. Shen, Y. Ota, S. Shin, M. Nakajima, S. Ishida, K. Kihou, C. H. Lee, A. Iyo, H. Eisaki, T. Mikami, T. Kakeshita, Y. Yamakawa, H. Kontani, S. Uchida, A. Fujimori

      Vol. 95 ( 10 ) page: 104504   2017.3

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    DOI: 10.1103/PhysRevB.95.104504

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  40. Low Carrier Density Metal Realized in Candidate Line-Node Dirac Semimetals CaAgP and CaAgAs Reviewed

    Okamoto Yoshihiko, Inohara Takumi, Yamakage Ai, Yamakawa Youichi, Takenaka Koshi

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 85 ( 12 )   2016.12

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

    DOI: 10.7566/JPSJ.85.123701

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  41. Functional renormalization group study of orbital fluctuation mediated superconductivity: Impact of the electron-boson coupling vertex corrections Reviewed

    Tazai Rina, Yamakawa Youichi, Tsuchiizu Masahisa, Kontani Hiroshi

    PHYSICAL REVIEW B   Vol. 94 ( 11 )   2016.9

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

    DOI: 10.1103/PhysRevB.94.115155

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  42. Synthesis and Superconducting Properties of a Hexagonal Phosphide ScRhP Reviewed

    Inohara Takumi, Okamoto Yoshihiko, Yamakawa Youichi, Takenaka Koshi

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 85 ( 9 )   2016.9

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

    DOI: 10.7566/JPSJ.85.094706

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  43. Theoretical prediction of nematic orbital-ordered state in the Ti oxypnictide superconductor BaTi2(As,Sb)(2)O Reviewed

    Nakaoka Hironori, Yamakawa Youichi, Kontani Hiroshi

    PHYSICAL REVIEW B   Vol. 93 ( 24 )   2016.6

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

    DOI: 10.1103/PhysRevB.93.245122

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  44. p-orbital density wave with d symmetry in high-T-c cuprate superconductors predicted by renormalization-group plus constrained RPA theory Reviewed

    Tsuchiizu Masahisa, Yamakawa Youichi, Kontani Hiroshi

    PHYSICAL REVIEW B   Vol. 93 ( 15 )   2016.4

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    DOI: 10.1103/PhysRevB.93.155148

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  45. Superconductivity in the Hexagonal Ternary Phosphide ScIrP Reviewed

    Okamoto Yoshihiko, Inohara Takumi, Yamakawa Youichi, Yamakage Ai, Takenaka Koshi

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 85 ( 1 )   2016.1

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

    DOI: 10.7566/JPSJ.85.013704

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  46. Line-Node Dirac Semimetal and Topological Insulating Phase in Noncentrosymmetric Pnictides CaAgX (X = P, As) Reviewed

    Yamakage Ai, Yamakawa Youichi, Tanaka Yukio, Okamoto Yoshihiko

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 85 ( 1 )   2016.1

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

    DOI: 10.7566/JPSJ.85.013708

    Web of Science

  47. Superconductivity pairing mechanism from cobalt impurity doping in FeSe: Spin (s±) or orbital (s++) fluctuation Reviewed

    T. Urata, Y. Tanabe, K. K. Huynh, Y. Yamakawa, H. Kontani, K. Tanigaki

    Physical Review B   Vol. 93 ( 1 ) page: 014507   2016.1

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    DOI: 10.1103/PhysRevB.93.014507

  48. Momentum-dependent sign inversion of orbital order in superconducting FeSe Reviewed

    Y. Suzuki, T. Shimojima, T. Sonobe, A. Nakamura, M. Sakano, H. Tsuji, J. Omachi, K. Yoshioka, M. Kuwata-Gonokami, T. Watashige, R. Kobayashi, S. Kasahara, T. Shibauchi, Y. Matsuda, Y. Yamakawa, H. Kontani, K. Ishizaka

    Physical Review B   Vol. 92 ( 20 ) page: 205117   2015.11

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    DOI: 10.1103/PhysRevB.92.205117

  49. Revisiting orbital-fluctuation-mediated superconductivity in LiFeAs: Nontrivial spin-orbit interaction effects on the band structure and superconducting gap function Reviewed

    Saito Tetsuro, Yamakawa Youichi, Onari Seiichiro, Kontani Hiroshi

    PHYSICAL REVIEW B   Vol. 92 ( 13 )   2015.10

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    DOI: 10.1103/PhysRevB.92.134522

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  50. Quasiparticle interference in Fe-based superconductors based on a five-orbital tight-binding model Reviewed

    Yamakawa Youichi, Kontani Hiroshi

    PHYSICAL REVIEW B   Vol. 92 ( 4 )   2015.7

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    DOI: 10.1103/PhysRevB.92.045124

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  51. Spin-Fluctuation-Driven Nematic Charge-Density Wave in Cuprate Superconductors: Impact of Aslamazov-Larkin Vertex Corrections Reviewed

    Yamakawa Youichi, Kontani Hiroshi

    PHYSICAL REVIEW LETTERS   Vol. 114 ( 25 ) page: 257001-1 - 257001-6   2015.6

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    DOI: 10.1103/PhysRevLett.114.257001

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  52. Spin-triplet superconductivity in Sr2RuO4 due to orbital and spin fluctuations: Analyses by two-dimensional renormalization group theory and self-consistent vertex-correction method Reviewed

    Tsuchiizu Masahisa, Yamakawa Youichi, Onari Seiichiro, Ohno Yusuke, Kontani Hiroshi

    PHYSICAL REVIEW B   Vol. 91 ( 15 )   2015.4

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    DOI: 10.1103/PhysRevB.91.155103

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  53. Quantum critical behavior in heavily doped LaFeAsO1-xHx pnictide superconductors analyzed using nuclear magnetic resonance Reviewed

    R. Sakurai, N. Fujiwara, N. Kawaguchi, Y. Yamakawa, H. Kontani, S. Iimura, S. Matsuishi, H. Hosono

    Physical Review B   Vol. 91 ( 6 ) page: 064509   2015.2

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    DOI: 10.1103/PhysRevB.91.064509

  54. Linear Response Theory for Shear Modulus C-66 and Raman Quadrupole Susceptibility: Evidence for Nematic Orbital Fluctuations in Fe-based Superconductors Reviewed

    Kontani Hiroshi, Yamakawa Youichi

    PHYSICAL REVIEW LETTERS   Vol. 113 ( 4 )   2014.7

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    DOI: 10.1103/PhysRevLett.113.047001

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  55. Reproduction of experimental gap structure in LiFeAs based on orbital-spin fluctuation theory: s(++)-wave, s(+/-)-wave, and hole-s(+/-)-wave states Reviewed

    Saito Tetsuro, Onari Seiichiro, Yamakawa Youichi, Kontani Hiroshi, Borisenko Sergey V., Zabolotnyy Volodymyr B.

    PHYSICAL REVIEW B   Vol. 90 ( 3 )   2014.7

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    DOI: 10.1103/PhysRevB.90.035104

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  56. High-T-c Superconductivity near the Anion Height Instability in Fe-Based Superconductors: Analysis of LaFeAsO1-xHx Reviewed

    Onari Seiichiro, Yamakawa Youichi, Kontani Hiroshi

    PHYSICAL REVIEW LETTERS   Vol. 112 ( 18 )   2014.5

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    DOI: 10.1103/PhysRevLett.112.187001

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  57. Zigzag Chain Structure Transition and Orbital Fluctuations in Ni-Based Superconductors Reviewed

    Yamakawa Youichi, Onari Seiichiro, Kontani Hiroshi

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 82 ( 9 )   2013.9

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    DOI: 10.7566/JPSJ.82.094704

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  58. Detection of Antiferromagnetic Ordering in Heavily Doped LaFeAsO1-xHx Pnictide Superconductors Using Nuclear-Magnetic-Resonance Techniques Reviewed

    N. Fujiwara, S. Tsutsumi, S. Iimura, S. Matsuishi, H. Hosono, Y. Yamakawa, H. Kontani

    Physical Review Letters   Vol. 111 ( 9 ) page: 097002   2013.8

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    DOI: 10.1103/PhysRevLett.111.097002

  59. Phase diagram and superconducting states in LaFeAsO1-xHx based on the multiorbital extended Hubbard model Reviewed

    Y. Yamakawa, S. Onari, H. Kontani, N. Fujiwara, S. Iimura, H. Hosono

    Physical Review B   Vol. 88 ( 4 ) page: 041106(R)   2013.7

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    DOI: 10.1103/PhysRevB.88.041106

  60. Effect of realistic finite-size impurities on T-c in Fe-based superconductors based on the five-orbital tight-binding model Reviewed

    Yamakawa Youichi, Onari Seiichiro, Kontani Hiroshi

    PHYSICAL REVIEW B   Vol. 87 ( 19 )   2013.5

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    DOI: 10.1103/PhysRevB.87.195121

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  61. Effect of inelastic scattering on the nuclear magnetic relaxation rate 1/T1T in iron-based superconductors Reviewed

    Yamakawa Youichi, Onari Seiichiro, Kontani Hiroshi

    SUPERCONDUCTOR SCIENCE & TECHNOLOGY   Vol. 25 ( 8 )   2012.8

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    DOI: 10.1088/0953-2048/25/8/084006

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  62. Impurity-induced electronic nematic state and C-2-symmetric nanostructures in iron pnictide superconductors Reviewed

    Inoue Yoshio, Yamakawa Youichi, Kontani Hiroshi

    PHYSICAL REVIEW B   Vol. 85 ( 22 )   2012.6

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    DOI: 10.1103/PhysRevB.85.224506

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  63. Orbital fluctuation theory in iron-based superconductors: s(++)-wave superconductivity, structure transition, and impurity-induced nematic order Reviewed

    Kontani Hiroshi, Inoue Yoshio, Saito Tetsuro, Yamakawa Youichi, Onari Seiichiro

    SOLID STATE COMMUNICATIONS   Vol. 152 ( 8 ) page: 718-727   2012.4

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    DOI: 10.1016/j.ssc.2012.01.012

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  64. Structural transition, ferro-orbital order and its fluctuation-mediated s(++)-wave superconductivity in iron pnictides Reviewed

    Ono Yoshiaki, Yanagi Yuki, Adachi Naoko, Yamakawa Youichi

    SOLID STATE COMMUNICATIONS   Vol. 152 ( 8 ) page: 701-710   2012.4

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    DOI: 10.1016/j.ssc.2012.01.017

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  65. Orbital Order, Structural Transition, and Superconductivity in Iron Pnictides Reviewed

    Yanagi Yuki, Yamakawa Youichi, Adachi Naoko, Ono Yoshiaki

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 79 ( 12 )   2010.12

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    DOI: 10.1143/JPSJ.79.123707

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  66. Cooperative effects of Coulomb and electron-phonon interactions in the two-dimensional 16-band d-p model for iron-based superconductors Reviewed

    Yanagi Yuki, Yamakawa Youichi, Adachi Naoko, Ono Yoshiaki

    PHYSICAL REVIEW B   Vol. 82 ( 6 )   2010.8

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    DOI: 10.1103/PhysRevB.82.064518

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  67. Two types of s-wave pairing due to magnetic and orbital fluctuations in the two-dimensional 16-band d-p model for iron-based superconductors Reviewed

    Yanagi Yuki, Yamakawa Youichi, Ono Yoshiaki

    PHYSICAL REVIEW B   Vol. 81 ( 5 )   2010.2

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    DOI: 10.1103/PhysRevB.81.054518

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  68. Antiferromagnetic, Charge and Orbital Order in Na0.5CoO2 Based on the Two Dimensional 11 Bands d-p Model Reviewed

    Yamakawa Youichi, Watanabe Naohiro, Ono Yoshiaki

    INTERNATIONAL CONFERENCE ON MAGNETISM (ICM 2009)   Vol. 200   2010

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  69. Effect of the spin-orbit interaction and the electron phonon coupling on the electronic state in a silicon vacancy Reviewed

    Yamada Takemi, Yamakawa Youichi, Ono Yoshiaki

    INTERNATIONAL CONFERENCE ON MAGNETISM (ICM 2009)   Vol. 200   2010

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  70. Structural Transition of Li2RuO3 Induced by Molecular-Orbit Formation Reviewed

    Miura Yoko, Sato Masatoshi, Yamakawa Youichi, Habaguchi Tatsuro, Ono Yoshiaki

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 78 ( 9 )   2009.9

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    DOI: 10.1143/JPSJ.78.094706

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  71. Quadrupole Susceptibility and Elastic Softening due to a Vacancy in Silicon Crystal Reviewed

    Yamada Takemi, Yamakawa Youichi, Ono Yoshiaki

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 78 ( 5 )   2009.5

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    DOI: 10.1143/JPSJ.78.054702

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  72. Cluster Model Calculations for Charge States of a Silicon Vacancy Reviewed

    Yamakawa Youichi, Ono Yoshiaki

    25TH INTERNATIONAL CONFERENCE ON LOW TEMPERATURE PHYSICS (LT25), PART 4   Vol. 150   2009

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    DOI: 10.1088/1742-6596/150/4/042233

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  73. Magnetism and Superconductivity in the Two-Dimensional 16-Band d-p Model for Iron-Based Superconductors Reviewed

    Yanagi Yuki, Yamakawa Youichi, Ono Yoshiaki

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 77 ( 12 )   2008.12

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    DOI: 10.1143/JPSJ.77.123701

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  74. Antiferromagnetic, charge and orbital ordered states of Na0.5CoO2 based on the two-dimensional triangular lattice d-p model Reviewed

    Yamakawa Youichi, Ono Yoshiaki

    JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS   Vol. 69 ( 12 ) page: 3349-3351   2008.12

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  75. Electronic states and pairing symmetry in the two-dimensional 16 band d-p model for iron-based superconductor Reviewed

    Yanagi Yuki, Yamakawa Youichi, Ono Yoshiaki

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 77   page: 149-150   2008.11

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  76. Effects of Electron Correlation and Electron-phonon Coupling on the quantum state of a Silicon Vacancy Reviewed

    Yamakawa Youichi, Mitsumoto Keisuke, Ono Yoshiaki

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 77   page: 266-268   2008.1

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    DOI: 10.1143/JPSJS.77SA.266

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▼display all

MISC 4

  1. 1次元ファンデルワールス結晶Ta4SiTe4における熱電効果 Invited Reviewed

    岡本佳比古 山川洋一 竹中康司

    固体物理   Vol. 59 ( 2 ) page: 41 - 51   2024.2

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    Language:Japanese   Publishing type:Article, review, commentary, editorial, etc. (trade magazine, newspaper, online media)   Publisher:株式会社 アグネ技術センター  

  2. 汎関数くりこみ群法による教相関電子系の研究 ー2次元電子系におけるネマティック秩序ー Invited Reviewed

    土射津昌久 田財里奈 山川洋一 紺谷浩

    固体物理   Vol. 55 ( 5 ) page: 195 - 203   2020.5

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  3. 軌道ネマティック秩序の理論―FeSeや各種鉄系超伝導体の統一的理解― Invited Reviewed

    山川洋一 紺谷浩

    固体物理   Vol. 51 ( 11 ) page: 77 - 92   2016.11

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    鉄系超伝導体において, 超伝導発現の母胎である正常電子状態の理解が急務であったが, その解明が急速に進んでいる. 特に 2013 年の FeSe における「非磁性電子ネマティック状態」の発見は, それまで標準理論とみなされてきたスピンネマティック理論の見直しを迫る出来事(パラダイムシフト)であり, スピン揺らぎと軌道揺らぎを対等に考慮する理論の進展のきっかけとなった. 本稿では, 平均場近似を超えた多体効果であるバーテックス補正を考慮した理論の進展を紹介する. 非磁性電子ネマティック秩序の正体は, バーテックス補正を起源とする新規な軌道秩序であり, 本理論に基づき FeSe をはじめ代表的な鉄系超伝導体が示すバラエティー豊かな相図が統一的に理解できる. さらに FeSe で実現する “符号反転軌道秩序”をはじめとする正常状態の key experiments が定量的に再現される.

  4. 高温超伝導体で起きる電子の液晶状態 Invited

    山川洋一

      Vol. 31   page: 16 - 17   2016.10

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    Authorship:Lead author   Language:Japanese   Publishing type:Article, review, commentary, editorial, etc. (bulletin of university, research institution)   Publisher:名古屋大学理学部・大学院理学研究科広報委員会  

Presentations 113

  1. Ginzburg-Landau理論に基づく磁場中相図および巨大外場応答の理解 Invited

    山川洋一

    日本物理学会 2024年春季大会  2024.3.21  日本物理学会

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    Event date: 2024.3

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

    Venue:online   Country:Japan  

  2. 電⼦ドープFeSeにおけるネマティック/スメクティック揺らぎ由来の⾼温超伝導:ボンド揺らぎと電⼦の強結 Invited

    ⼭川洋⼀, 大成誠一郎, 紺谷浩

    京都⼤学基礎物理学研究所研究会 「⾮⾃明な電⼦状態が⽣み出す超伝導現象の最前線:新たな挑戦と展望」  2021.12.22 

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    Event date: 2021.12

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

    Venue:京都大学   Country:Japan  

  3. Odd-parity bond-order and emergent transport phenomena in Ti-based kagome metal

    Jianxin Huang, Rina Tazai, Youichi Yamakawa, Takahiro Morimoto, Hiroshi Kontani

    2024.3.18 

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    Event date: 2024.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Country:Japan  

  4. カゴメ格子金属の電流秩序状態における不純物効果:電流分布及び軌道磁化の解析

    中沢正剛, 田財里奈, 山川洋一, 大成誠一郎, 紺谷浩

    日本物理学会 2024年春季大会  2024.3.18  日本物理学会

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    Event date: 2024.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:online   Country:Japan  

  5. カゴメ金属のループ電流に由来する非相反輸送現象の理論

    田財里奈, 山川洋一, 森本高裕, 紺谷浩

    日本物理学会 2024年春季大会  2024.3.20  日本物理学会

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    Event date: 2024.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:online   Country:Japan  

  6. 立方晶ReSTeの熱電特性と元素置換効果Ⅱ

    松本遥, 山川洋一, 廣井善二, 岡本佳比古

    日本物理学会 2024年春季大会  2024.3.20  日本物理学会

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    Event date: 2024.3

    Language:Japanese   Presentation type:Poster presentation  

    Venue:online   Country:Japan  

  7. Mechanism of Loop Current Order in Kagome metals AV3Sb5 International conference

    Rina Tazai, Youichi Yamakawa, Seiichiro Onari, Hiorshi Kontani

    APS March Meeting 2024  2024.3.7  American Physical Society

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    Event date: 2024.3

    Language:English   Presentation type:Oral presentation (general)  

    Venue:Minneapolis, MN, USA   Country:United States  

  8. Drastic magnetic-field-induced chiral current order and emergent current-bond-field interplay in kagome metals International conference

    Hiroshi Kontani, Rina Tazai, Youichi Yamakawa

    APS March Meeting 2024  2024.3.6  American Physical Society

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    Event date: 2024.3

    Language:English   Presentation type:Oral presentation (general)  

    Venue:Minneapolis, MN, USA   Country:United States  

  9. Nematic-Fluctuation-Driven Superconductivity and Quantum Criticality in Fe-Based Superconductors International conference

    Youichi Yamakawa, Rina Tazai, Hiroshi Kontani

    APS March Meeting 2024  2024.3.7  American Physical Society

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    Event date: 2024.3

    Language:English   Presentation type:Oral presentation (general)  

    Venue:Minneapolis, MN, USA   Country:United States  

  10. Three-dimensional CDW order in kagome metal: Three-dimensional DW equation analysis

    Seiichiro Onari, Rina Tazai, Youichi Yamakawa, Hiroshi Kontani

    2023.12.27 

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    Event date: 2023.12

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  11. Nematic Quantum Fluctuation Driven High-Tc Superconductivity in Fe-Based Superconductors

    Youichi Yamakawa, Hiroshi Kontani

    2023.12.27 

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    Event date: 2023.12

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  12. カゴメ金属における自発ループ電流の温度依存性およびfilling 依存性の理論

    志村昂輝, 田財里奈, 山川洋一, 大成誠一郎, 紺谷浩

    京都大学基礎物理学研究所研究会「超伝導研究の発展と広がり」  2023.12.21 

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    Event date: 2023.12

    Language:Japanese   Presentation type:Poster presentation  

    Venue:京都大学   Country:Japan  

  13. ネマティック量子揺らぎによる鉄系超伝導体の高温超伝導

    山川洋一, 紺谷浩

    京都大学基礎物理学研究所研究会「超伝導研究の発展と広がり」  2023.12.21 

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    Event date: 2023.12

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:京都大学   Country:Japan  

  14. Even- and Odd-parity Intra-unit-cell Bond-order and Emergent Nematicity and transport phenomena in kagome metals

    Huang Jianxin, Tazai Rina, Youichi Yamakawa, Seiichiro Onari, Hiroshi Kontani

    2023.12.21 

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    Event date: 2023.12

    Language:English   Presentation type:Poster presentation  

    Country:Japan  

  15. カゴメ金属の電流秩序状態における不純物効果:電流分布変化および局所磁化の発生

    中沢正剛, 田財里奈, 山川洋一, 大成誠一郎, 紺谷浩

    京都大学基礎物理学研究所研究会「超伝導研究の発展と広がり」  2023.12.21 

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    Event date: 2023.12

    Language:Japanese   Presentation type:Poster presentation  

    Venue:京都大学   Country:Japan  

  16. Emergence of Even- and Odd-Parity Intra-Unit-Cell Bond-Order and Nematicity in Kagome Metals

    Jianxin Huang, Rina Tazai, Youichi Yamakawa, Seiichiro Onari, Hiroshi Kontani

    2023.9.16 

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    Event date: 2023.9

    Language:English   Presentation type:Oral presentation (general)  

    Country:Japan  

  17. カゴメ金属のループカレント相における電流分布と軌道磁化

    志村昂輝, 田財里奈, 山川洋一, 大成誠一郎, 紺谷浩

    日本物理学会 第78回年次大会  2023.9.16  日本物理学会

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    Event date: 2023.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:東北大学   Country:Japan  

  18. カゴメ超伝導体における電荷ループ秩序,ボンド秩序とその共存相:ボンド揺らぎによる理論

    田財里奈, 山川洋一, 紺谷浩

    日本物理学会 第78回年次大会  2023.9.16  日本物理学会

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    Event date: 2023.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:東北大外   Country:Japan  

  19. カゴメ格子金属AV3Sb5(A=Cs,Rb,K)における電流・ボンド・磁場間相互作用に起因した顕著な磁場誘起ループ電流秩序

    山川洋一, 田財里奈, 紺谷浩

    日本物理学会 第78回年次大会  2023.9.16  日本物理学会

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    Event date: 2023.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:東北大学   Country:Japan  

  20. カゴメ金属における3次元CDW秩序:GL理論の3次項の解析

    大成誠一郎, 山川洋一, 田財里奈, 紺谷浩

    日本物理学会 第78回年次大会  2023.9.16  日本物理学会

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    Event date: 2023.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:東北大外   Country:Japan  

  21. 金属化されたキタエフハニカム模型における電子相関効果:スピン軌道相互作用の役割

    橋本敬宏, 山川洋一, 大成誠一郎, 紺谷浩

    日本物理学会 第78回年次大会  2023.9.18  日本物理学会

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    Event date: 2023.9

    Language:Japanese   Presentation type:Poster presentation  

    Venue:東北大学   Country:Japan  

  22. カゴメ格子金属 AV3Sb5 (A = Cs, Rb, K) における電流・ボンド・磁場間相互作用に起因した顕著な磁場誘起ループ電流秩序

    山川洋一, 田財里奈, 紺谷浩

    高温超伝導フォーラム第11回会合  2023.9.15  高温超伝導フォーラム

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    Event date: 2023.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:東北大学   Country:Japan  

  23. カゴメ超伝導体における電荷ループ秩序の理論

    田財里奈, 山川洋一, 紺谷浩

    高温超伝導フォーラム第11回会合  2023.9.15  高温超伝導フォーラム

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    Event date: 2023.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:東北大学   Country:Japan  

  24. カゴメ金属のループカレント相における実空間電流分布

    志村昂輝, 田財里奈, 山川洋一, 大成誠一郎, 紺谷浩

    研究会「強相関電子系のフロンティア」  2023.8.21  大成誠一郎, 酒井志朗

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    Event date: 2023.8

    Language:Japanese   Presentation type:Poster presentation  

    Venue:名古屋大学   Country:Japan  

  25. ネマティック量子臨界点近傍における非フェルミ液体と超伝導発現機構 Invited

    山川洋一

    研究会「強相関電子系のフロンティア」  2023.8.22  大成誠一郎, 酒井志朗

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    Event date: 2023.8

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

    Venue:名古屋大学   Country:Japan  

  26. Even- and Odd-Parity Intra-Unit-Cell Bond-Order and Emergence Nematicity in Kagome Metals

    Huang Jianxin, Tazai Rina, Youichi Yamakawa, Seiichiro Onari, Hiroshi Kontani

    2023.8.21 

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    Event date: 2023.8

    Language:English   Presentation type:Poster presentation  

    Country:Japan  

  27. 金属化されたキタエフハニカム模型における電子相関効果:スピン軌道相互作用の役割」

    橋本敬宏, 山川洋一, 紺谷浩

    研究会「強相関電子系のフロンティア」  2023.8.21  大成誠一郎, 酒井志朗

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    Event date: 2023.8

    Language:Japanese   Presentation type:Poster presentation  

    Venue:名古屋大学   Country:Japan  

  28. Even- and Odd-Parity Intra-Unit-Cell Bond-Order and Emergence Nematicity in Kagome Metals International conference

    Jianxin Huang, Rina Tazai, Youichi Yamakawa, Seiichiro Onari, Hiroshi Kontani

    International Conference on Quantum Liquid Crystals 2023 (QLC2023)  2023.8.9  Takasada Shibauchi, Tsuyoshi Kimura, Yasunori Toda

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    Event date: 2023.8

    Language:English   Presentation type:Poster presentation  

    Venue:Hokaaido University   Country:Japan  

  29. Drastic magnetic-field-induced chiral current order and emergent current-bond-field interplay in kagome metalAV3Sb5 (A=Cs,Rb,K) International conference

    Youichi Yamakawa, Rina Tazai, Hiroshi Kontani

    International Conference on Quantum Liquid Crystals 2023 (QLC2023)  2023.8.9  Takasada Shibauchi, Tsuyoshi Kimura, Yasunori Toda

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    Event date: 2023.8

    Language:English   Presentation type:Poster presentation  

    Country:Japan  

  30. Three-dimensional CDW order in kagome metal: Analysis of third-order term in three-dimensional GL theory International conference

    Seiichiro Onari, Rina Tazai, Youichi Yamakawa, Hiroshi Kontani

    International Conference on Quantum Liquid Crystals 2023 (QLC2023)  2023.8.9  Takasada Shibauchi, Tsuyoshi Kimura, Yasunori Toda

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    Event date: 2023.8

    Language:English   Presentation type:Poster presentation  

    Venue:Hokaaido University   Country:Japan  

  31. Nematic Fluctuation Driven Quantum Criticality and High-Tc Superconductivity: Fe-based and Cuprate Superconductors International conference

    Youichi Yamakawa, Seiichiro Onari, Hiroshi Kontani

    International Conference on Strongly Correlated Electron Systems (SCES 2023)  2023.7.3  The Korean Physical Society

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    Event date: 2023.7

    Language:English   Presentation type:Poster presentation  

    Venue:Songdo Convensia, Incheon, Korea   Country:Korea, Republic of  

  32. GL理論に基づくカゴメ格子金属AV3Sb5(A=Cs,Rb,K)の多重量子相の解析

    山川洋一, 田財里奈, 小川明里, 大成誠一郎, 紺谷浩

    日本物理学会 2023年春季大会  2023.3.22 

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    Event date: 2023.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:東京工業大学   Country:Japan  

  33. 量子液晶の臨界点近傍における非フェルミ液体的輸送現象と超伝導機構

    山川洋一, 大成誠一郎, 紺谷浩

    日本物理学会 2023年春季大会  2023.3.25 

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    Event date: 2023.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:東京工業大学   Country:Japan  

  34. キャリアドープされたスピン系α-RuCl3における超伝導状態の理論解析

    橋本敬宏, 山川洋一, 大成誠一郎, 紺谷浩

    日本物理学会 2023年春季大会  2023.3.24 

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    Event date: 2023.3

    Language:Japanese   Presentation type:Poster presentation  

    Venue:東京工業大学   Country:Japan  

  35. 2次元カゴメ格子系のcharge loop current相における実空間電流構造

    志村昂輝, 田財里奈, 山川洋一, 大成誠一郎, 紺谷浩

    日本物理学会 2023年春季大会  2023.3.24 

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    Event date: 2023.3

    Language:Japanese   Presentation type:Poster presentation  

    Venue:東京工業大学   Country:Japan  

  36. 超伝導体Sc6MTe2(M = Fe,Co,Ni)の元素置換効果

    岡本佳比古, 篠田祐作, 松本遥, 山川洋一, 平井大悟郎, 竹中康司

    日本物理学会 2023年春季大会  2023.3.24 

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    Event date: 2023.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:東京工業大学   Country:Japan  

  37. カゴメ金属における3次元CDW秩序の理論解析

    大成誠一郎, 山川洋一, 田財里奈, 紺谷浩

    日本物理学会 2023年春季大会  2023.3.24 

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    Event date: 2023.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:東京工業大学   Country:Japan  

  38. Theoretical analysis of nematic state due to the mix-type band electron correlation in kagome metal AV3Sb5

    Jianxin Huang, Rina TazaiA, Youichi Yamakawa, Seiichiro Onari, Hiroshi Kontani

    2023.3.22 

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    Event date: 2023.3

    Language:English   Presentation type:Oral presentation (general)  

    Country:Japan  

  39. Theoretical analysis of nematic state due to the mix-type band electron correlation in kagome metal AV3Sb5

    Jianxin Huang, Rina TazaiA, Youichi Yamakawa, Seiichiro Onari, Hiroshi Kontani

    2023.3.22 

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    Event date: 2023.3

    Language:English   Presentation type:Oral presentation (general)  

    Country:Japan  

  40. Theoretical analysis of nematic state due to the mix-type band electron correlation in kagome metal AV3Sb5

    Jianxin Huang, Rina TazaiA, Youichi Yamakawa, Seiichiro Onari, Hiroshi Kontani

    2023.3.22 

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    Event date: 2023.3

    Language:English   Presentation type:Oral presentation (general)  

    Country:Japan  

  41. Theoretical analysis of nematic state due to the mix-type band electron correlation in kagome metal AV3Sb5

    Jianxin Huang, Rina TazaiA, Youichi Yamakawa, Seiichiro Onari, Hiroshi Kontani

    2023.3.22 

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    Event date: 2023.3

    Language:English   Presentation type:Oral presentation (general)  

    Country:Japan  

  42. Theoretical analysis of nematic state due to the mix-type band electron correlation in kagome metal AV3Sb5

    Jianxin Huang, Rina TazaiA, Youichi Yamakawa, Seiichiro Onari, Hiroshi Kontani

    2023.3.22 

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    Event date: 2023.3

    Language:English   Presentation type:Oral presentation (general)  

    Country:Japan  

  43. Mechanism of even- and odd-parity density-waves and beyond-Migdal superconductivity in kagome metal AV3Sb5 (A = K, International conference

    H. Kontani, R. Tazai, Y. Yamakawa, S. Onari

    APS March Meeting 2023  2023.3.8 

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    Event date: 2023.3

    Language:English   Presentation type:Oral presentation (general)  

    Venue:Las Vegas, USA   Country:United States  

  44. Nematic fluctuation driven quantum criticality and superconductivity: Fe-based and cuprate superconductors International conference

    Y. Yamakawa, S. Onari, H. Kontani

    APS March Meeting 2023  2023.3.10 

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    Event date: 2023.3

    Language:English   Presentation type:Oral presentation (general)  

    Venue:Las Vegas, USA   Country:United States  

  45. Emergence of XY-nematic state due to the mix-type band electron correlation in kagome metal AV3Sb5

    Huang Jianxin, Tazai Rina, Youichi Yamakawa, Seiichiro Onari, Hiroshi Kontani

    2022.12.22 

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    Event date: 2022.12

    Language:English   Presentation type:Poster presentation  

    Country:Japan  

  46. カゴメ超伝導体AV3Sb5における時間反転対称性の破れとネマティック相の起源 Invited

    田財里奈, 山川洋一, 紺谷浩

    基研研究会「非自明な電子状態で発現する超伝導現象の新しい潮流」  2022.12.22 

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    Event date: 2022.12

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

    Venue:京都大学   Country:Japan  

  47. 量子液晶揺らぎによる量子臨界現象と超伝導の理論研究

    山川洋一, 大成誠一郎, 紺谷浩

    基研研究会「非自明な電子状態で発現する超伝導現象の新しい潮流」  2022.12.21 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:京都大学   Country:Japan  

  48. カゴメ金属AV3Sb5の磁場中相図の理論的考察

    紺谷浩, 山川洋一, 田財里奈, 大成誠一郎

    基研研究会「非自明な電子状態で発現する超伝導現象の新しい潮流」  2022.12.22 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Poster presentation  

    Venue:京都大学   Country:Japan  

  49. キャリアドープされたキタエフスピン系α-RuCl3における金属状態の理論計算

    橋本敬宏, 山川洋一, 大成誠一郎, 紺谷浩

    基研研究会「非自明な電子状態で発現する超伝導現象の新しい潮流」  2022.12.22 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Poster presentation  

    Venue:京都大学   Country:Japan  

  50. カゴメ格子系の電流秩序相における実空間電流分布の研究

    志村昂輝, 田財里奈, 山川洋一, 大成誠一郎, 紺谷浩

    基研研究会「非自明な電子状態で発現する超伝導現象の新しい潮流」  2022.12.22 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Poster presentation  

    Venue:京都大学   Country:Japan  

  51. Superconductivity in hexagonal scandium compounds

    Yusaku Shinoda, Yoshihiko Okamoto, Daigorou Hirai, Youich Yamakawa and Koshi Takenaka

    2022.12.9 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  52. Theory of nematic fluctuation driven quantum criticality and superconductivity

    Youichi Yamakawa, Seiichiro Onari, and Hiroshi Kontani

    2022.12.9 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  53. Theory of Bond, Loop Current and Superconductivity in Kagome Metal AV3Sb5

    Rina Tazai , Youichi Yamakawa, Seiichiro Onari and Hiroshi Kontani

    2022.12.9 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  54. Emergence of XY-nematic state due to the mix-type band electron correlation in kagome metal AV3Sb5

    Huang Jianxin, Tazai Rina, Youichi Yamakawa, Seiichiro Onari, Hiroshi Kontani

    2022.12.9 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  55. Novel quantum liquid crystal states in recently discovered strongly correlated metals

    Hiroshi Kontani, Rina Tazai, Youichi Yamakawa, Seiichiro Onari

    2022.12.10 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Oral presentation (general)  

    Country:Japan  

  56. Superconductivity in Ternary Scandium Tellurides with 3d, 4d, and 5d Transition Metals

    Yoshihiko Okamoto, Yusaku Shinoda, Haruka Matsumoto, Youichi Yamakawa, Daigorou Hirai, and Koshi Takenaka

    2022.12.8 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Oral presentation (general)  

    Country:Japan  

  57. Theory of multiple quantum phases in kagome metal : Analysis by the Ginzburg-Landau theory

    A. Ogawa, R. Tazai, Y. Yamakawa, S. Onari and H. Kontani

    2022.12.9 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  58. 二層系銅酸化物超伝導体のCDW状態の理論:バーテックス補正と自己エネルギーの効果

    横田奏帆, 山川洋一, 大成誠一郎, 紺谷浩

    日本物理学会 2022年秋季大会  2022.9.13 

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    Event date: 2022.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:東京工業大学   Country:Japan  

  59. ネマティック量子臨界現象の理論解析:異常輸送現象,有効質量増強,高温超伝導現象

    山川洋一, 大成誠一郎, 紺谷浩

    日本物理学会 2022年秋季大会  2022.9.14 

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    Event date: 2022.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:東京工業大学   Country:Japan  

  60. Ginzburg-Landau理論に基づくカゴメ金属の多重量子相の解析

    小川明里, 田財里奈, 山川洋一, 大成誠一郎, 紺谷浩

    日本物理学会 2022年秋季大会  2022.3.13 

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    Event date: 2022.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:東京工業大学   Country:Japan  

  61. カゴメ金属AV3Sb5における電荷・超伝導・時間反転対称性の破れの起源

    田財里奈, 山川洋一, 大成誠一郎, 紺谷浩

    日本物理学会 2022年秋季大会  2022.3.13 

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    Event date: 2022.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:東京工業大学   Country:Japan  

  62. Nematic critical phenomena in Fe-based superconductors based on Bethe-Salpeter equation method International conference

    Y. Yamakawa, S. Onari, H. Kontani

    29th International Conference on Low Temperature Physics (LT29)  2022.8.22 

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    Event date: 2022.8

    Language:English   Presentation type:Poster presentation  

    Country:Japan  

  63. Theory of multiple quantum phase in kagome metal: Analysis by the Ginzburg-Landau theory International conference

    Akari Ogawa, Rina Tazai, Youichi Yamakawa, Seiichiro Onari, Hiroshi Kontani

    29th International Conference on Low Temperature Physics (LT29)  2022.8.20 

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    Event date: 2022.8

    Language:English   Presentation type:Poster presentation  

    Country:Japan  

  64. Bond-order formation in double-layered cuprates due to spin fluctuation interference mechanism International conference

    Kanaho Yokota, Youichi Yamakawa, Seiichiro Onari, Hiroshi Kontani

    29th International Conference on Low Temperature Physics (LT29)  2022.8.20 

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    Event date: 2022.8

    Language:English   Presentation type:Poster presentation  

    Country:Japan  

  65. Microscopic theory of nematicity in FeSe: Lifshitz transition, tiny specific heat jump at TS and nematic criticality International conference

    R. Tazai, S. Matsubara, Y. Yamakawa, S. Onari, H. Kongani

    29th International Conference on Low Temperature Physics (LT29)  2022.8.22 

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    Event date: 2022.8

    Language:English   Presentation type:Poster presentation  

    Country:Japan  

  66. FeSe系におけるNematic/Smectic揺らぎが媒介する強結合高温超伝導

    山川洋一, 大成誠一郎, 紺谷浩

    日本物理学会 第77回年次大会 (2022年)  2022.3.15 

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    Event date: 2022.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  67. ScMM'( M = Pd, Pt, M' = Si, Ge )における超伝導

    篠田祐作, 岡本佳比古, 高津浩, 陰山洋, 山川洋一, 竹中康司

    日本物理学会 第77回年次大会 (2022年)  2022.3.16 

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    Event date: 2022.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  68. フラストレートカゴメ金属におけるCDW秩序の理論:Ginzburg-Landau理論に基づく解析

    小川明里, 紺谷浩, 大成誠一郎, 山川洋一, 田財里奈

    日本物理学会 第77回年次大会 (2022年)  2022.3.16 

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    Event date: 2022.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  69. 低温用熱電変換材料Ta4SiTe4の光反射分光

    松永文弥, 岡本佳比古, 横山泰範, 吉川侑磨, 竹端寛治, 今中康貴, 山川洋一, 竹中康司

    日本物理学会 第77回年次大会 (2022年)  2022.3.15 

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    Event date: 2022.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  70. 二層系銅酸化物高温超伝導体のCDW状態の理論:密度波方程式による解析

    横田奏帆, 山川洋一, 大成誠一郎, 紺谷浩

    日本物理学会 第77回年次大会 (2022年)  2022.3.15 

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    Event date: 2022.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  71. カゴメ超伝導体AV3Sb5における電荷秩序と非従来型超伝導の包括的理解

    田財里奈, 山川洋一, 大成誠一郎, 紺谷浩

    日本物理学会 第77回年次大会 (2022年)  2022.3.15 

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    Event date: 2022.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  72. Quasiparticle coherence in nematic state studied with strain-dependent ARPES International conference

    Rina Tazai, Hiroshi Kontani, Youichi Yamakawa, Seiichiro Onari

    APS March Meeting 2022  2022.3.15 

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    Event date: 2022.3

    Language:English   Presentation type:Oral presentation (general)  

    Venue:online   Country:United States  

  73. Nematic electronic states under TS and superconducting mechanism near nematic QCP in FeSe family International conference

    Hiroshi Kontani, Seiichiro Onari, Youichi Yamakawa, Shun Matsubara

    APS March Meeting 2022  2022.3.18 

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    Event date: 2022.3

    Language:English   Presentation type:Oral presentation (general)  

    Venue:online   Country:United States  

  74. 鉄系超伝導体におけるネマティック量子臨界現象と超伝導

    山川洋一, 大成誠一郎, 紺谷浩

    高温超伝導フォーラム第9回会合   2022.3.14 

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    Event date: 2022.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  75. 新規カゴメ超伝導 AV 3 Sb 5 における電荷秩序と超伝導相の理論研究

    田財里奈, 山川洋一, 大成誠一郎, 紺谷浩

    高温超伝導フォーラム第9回会合   2022.3.14 

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    Event date: 2022.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  76. Novel QLC states in Fe-based SCs, kagome metals, and magic angle twisted bilayer graphene

    H. Kontani, S. Matsubara, R. Tazai, Y.Yamakawa, S. Onari

    2022.2.18 

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    Event date: 2022.2

    Language:Japanese   Presentation type:Oral presentation (keynote)  

    Country:Japan  

  77. Strong coupling high-Tc superconductivity mediated by nematic/smectic fluctuations in FeSe systems

    Y Yamakawa, S. Onari, and H. Kontani

    2022.2.18 

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    Event date: 2022.2

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  78. Bond-Order Formation in Double-Layered Cuprates due to Spin Fluctuation Interference Mechanism

    K. Yokota,Y. Yamakawa,S. Onari,H. Kontani

    2022.2.18 

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    Event date: 2022.2

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  79. CDW order in kagome metal : Analysis by Ginzburg-Landau theory

    A. Ogawa, R. Tazai, Y. Yamakawa, S. Onari, H. Kontani

    2022.2.18 

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    Event date: 2022.2

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  80. Non-Trivial Interplay between Unconventional CDW and Superconductivity in Kagome Metal AV3Sb5

    R. Tazai, Y. Yamakawa, S. Onari, H. Kontani

    2022.2.18 

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    Event date: 2022.2

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  81. Observation of Electronic Nematicity in the Dirac Semimetal BaNiS2

    C. J. Butler, Y. Kohsaka, Y. Yamakawa, M. S. Bahramy, S. Onari, H. Kontani, T. Hanaguri, S. Shamoto

    2022.2.18 

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    Event date: 2022.2

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  82. 新規カゴメ⾦属AV3Sb5における超伝導・電荷秩序相の研究

    田財里奈, 山川洋一, 大成誠一郎, 紺谷浩

    京都⼤学基礎物理学研究所研究会 「⾮⾃明な電⼦状態が⽣み出す超伝導現象の最前線:新たな挑戦と展望」  2021.12.22 

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    Event date: 2021.12

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

    Venue:京都大学   Country:Japan  

  83. Ginzburg-Landau理論に基づくカゴメ系のCDW秩序の理論研究

    ⼩川明⾥, 田財里奈, 山川洋一, 大成誠一郎, 紺谷浩

    京都⼤学基礎物理学研究所研究会 「⾮⾃明な電⼦状態が⽣み出す超伝導現象の最前線:新たな挑戦と展望」  2021.12.23 

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    Event date: 2021.12

    Language:Japanese   Presentation type:Poster presentation  

    Venue:京都大学   Country:Japan  

  84. ⼆層系銅酸化物⾼温超伝導体の電⼦状態の解析

    横田奏帆, 山川洋一, 大成誠一郎, 紺谷浩

    京都⼤学基礎物理学研究所研究会 「⾮⾃明な電⼦状態が⽣み出す超伝導現象の最前線:新たな挑戦と展望」  2021.12.23 

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    Event date: 2021.12

    Language:Japanese   Presentation type:Poster presentation  

    Venue:京都大学   Country:Japan  

  85. 構造因子の最適化法による各種量子液晶転移の多体理論の研究

    田財里奈, 山川洋一, 大成誠一郎, 紺谷浩

    日本物理学会 2021年秋季大会  2021.9.20 

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    Event date: 2021.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  86. 鉄系超伝導体におけるネマティック/スメクティック揺らぎと超伝導の理論研究

    山川洋一, 大成誠一郎, 紺谷浩

    日本物理学会 2021年秋季大会  2021.9.23 

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    Event date: 2021.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  87. 銅酸化物高温超伝導体における反強d波ボンド秩序下の多体電子状態

    安藤叡史, 山川洋一, 大成誠一郎, 紺谷浩

    日本物理学会 2021年秋季大会  2021.9.21 

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    Event date: 2021.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  88. Analysis of phase diagram in FeSe1-xTex International conference

    Seiichiro Onari, Youichi Yamakawa, and Hiroshi Kontani

    International Conference on Quantum Liquid Crystals 2021 (QLC2021)  2021.5.11  Takasada Shibauchi, Tsuyoshi Kimura

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    Event date: 2021.5

    Language:English   Presentation type:Poster presentation  

    Venue:online   Country:Japan  

  89. Observation of Electronic Nematic Order in the Correlated Dirac Semimetal BaNiS2 International conference

    C. J. Butler, Y. Kohsaka, M. S. Bahramy, Y. Yamakawa, S. Onari, H. Kontani, T. Hanaguri, and S. Shamoto

    International Conference on Quantum Liquid Crystals 2021 (QLC2021)  2021.5.13  Takasada Shibauchi, Tsuyoshi Kimura

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    Event date: 2021.5

    Language:English   Presentation type:Poster presentation  

    Venue:online   Country:Japan  

  90. Unconventional orbital-charge density wave mechanism in transition metal dichalcogenide 1T-TaS2 International conference

    Youichi Yamakawa, Toru Hirata, Seiichiro Onari, and Hiroshi Kontani

    International Conference on Quantum Liquid Crystals 2021 (QLC2021)  2021.5.13  Takasada Shibauchi, Tsuyoshi Kimura

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    Event date: 2021.5

    Language:English   Presentation type:Poster presentation  

    Venue:online   Country:Japan  

  91. Unified Description of Bond- and Charge/Spin Loop Current Orders: Importance of Form Factor and Vertex Corrections International conference

    Rina Tazai, Youichi Yamakawa, Seiichiro Onari and Hiroshi Kontani

    International Conference on Quantum Liquid Crystals 2021 (QLC2021)  2021.5.13  Takasada Shibauchi, Tsuyoshi Kimura

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    Event date: 2021.5

    Language:English   Presentation type:Oral presentation (general)  

    Venue:online   Country:Japan  

  92. Development of spin fluctuation under the presence of d-wave bond order in cuprate superconductors International conference

    Satoshi Ando, Youichi Yamakawa, Seiichiro Onari and Hiroshi Kontani

    International Conference on Quantum Liquid Crystals 2021 (QLC2021)  2021.5.12  Takasada Shibauchi, Tsuyoshi Kimura

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    Event date: 2021.5

    Language:English   Presentation type:Poster presentation  

    Venue:online   Country:Japan  

  93. Observation of Electronic Nematic Order in the Correlated Dirac Semimetal BaNiS2 International conference

    C. J. Butler, Y. Kohsaka, M. S. Bahramy, Y. Yamakawa, S. Onari, H. Kontani, T. Hanaguri, and S. Shamoto

    International Conference on Quantum Liquid Crystals 2021 (QLC2021)  2021.5.13  Takasada Shibauchi, Tsuyoshi Kimura

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    Event date: 2021.5

    Language:English   Presentation type:Poster presentation  

    Venue:online   Country:Japan  

  94. Unconventional orbital-charge density wave mechanism in transition metal dichalcogenide 1T-TaS2 International conference

    Youichi Yamakawa, Toru Hirata, Seiichiro Onari, and Hiroshi Kontani

    International Conference on Quantum Liquid Crystals 2021 (QLC2021)  2021.5.13  Takasada Shibauchi, Tsuyoshi Kimura

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    Event date: 2021.5

    Language:English   Presentation type:Poster presentation  

    Venue:online   Country:Japan  

  95. Unified Description of Bond- and Charge/Spin Loop Current Orders: Importance of Form Factor and Vertex Corrections International conference

    Rina Tazai, Youichi Yamakawa, Seiichiro Onari and Hiroshi Kontani

    International Conference on Quantum Liquid Crystals 2021 (QLC2021)  2021.5.13  Takasada Shibauchi, Tsuyoshi Kimura

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    Event date: 2021.5

    Language:English   Presentation type:Oral presentation (general)  

    Venue:online   Country:Japan  

  96. Development of spin fluctuation under the presence of d-wave bond order in cuprate superconductors International conference

    Satoshi Ando, Youichi Yamakawa, Seiichiro Onari and Hiroshi Kontani

    International Conference on Quantum Liquid Crystals 2021 (QLC2021)  2021.5.12  Takasada Shibauchi, Tsuyoshi Kimura

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    Event date: 2021.5

    Language:English   Presentation type:Poster presentation  

    Venue:online   Country:Japan  

  97. Theory of charge loop current in quasi-one-dimensional systems based on functional renormalization group study International conference

    Rina Tazai, Youichi Yamakawa, Hiroshi Kontani

    APS March Meeting 2021  2021.3.16 

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    Event date: 2021.3

    Language:English   Presentation type:Oral presentation (general)  

    Country:United States  

  98. Unconventional orbital-charge density wave mechanism in transition metal dichalcogenide 1T-TaS2 International conference

    Toru Hirata, Youichi Yamakawa, Seiichiro Onari, Hiroshi Kontani

    APS March Meeting 2021  2021.3.16 

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    Event date: 2021.3

    Language:English   Presentation type:Oral presentation (general)  

    Country:United States  

  99. 元素置換したノーダルライン半金属CaAgPに現れる高移動度キャリアと超伝導

    岡本佳比古, 三枝一茂, 篠田祐作, 山影相, 山川洋一, 笹川崇男, 片山尚幸, 高津浩C, 陰山洋, 竹中康司

    日本物理学会 第76回年次大会(2021年)  2021.3.14 

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    Event date: 2021.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:online   Country:Japan  

  100. 磁気フラストレーション系の電荷ループ相の理論研究

    田財里奈, 山川洋一, 紺谷浩

    日本物理学会 第76回年次大会(2021年)  2021.3.14 

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    Event date: 2021.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:online   Country:Japan  

  101. 鉄系超伝導体における電子相関とフォノンの協力による超伝導機構

    山川洋一, 大成誠一郎, 紺谷浩

    日本物理学会 第76回年次大会(2021年)  2021.3.14 

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    Event date: 2021.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:online   Country:Japan  

  102. Unconventional orbital-charge density wave mechanism in transition metal dichalcogenide 1T-TaS2

    2020.12.22 

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    Event date: 2020.12

    Language:English   Presentation type:Poster presentation  

    Country:Japan  

  103. Theoretical Study for Charge Loop Current in Geometrically Frustrated Electron System

    2020.12.22 

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    Event date: 2020.12

    Language:English   Presentation type:Poster presentation  

    Country:Japan  

  104. Effects of bond/CDW order on SC state in the square lattice model

    2020.12.22 

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    Event date: 2020.12

    Language:English   Presentation type:Poster presentation  

    Country:Japan  

  105. 強相関電子系における各種カレント秩序相の微視的機構の研究 -汎関数くりこみ群を中心に- Invited

    田財里奈、山川洋一、土射津昌久、大成誠一郎、紺谷浩

    京都大学基礎物理学研究所研究会「高温超伝導・非従来型超伝導研究の最前線:多様性と普遍性」  2020.10.28 

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    Event date: 2020.10

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

    Venue:京都大学   Country:Japan  

  106. 鉄系超伝導体における電子相関とフォノンの協力機構:フォームファクターの重要性

    山川洋一、大成誠一郎、紺谷浩

    京都大学基礎物理学研究所研究会「高温超伝導・非従来型超伝導研究の最前線:多様性と普遍性」  2020.10.27 

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    Event date: 2020.10

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:online   Country:Japan  

  107. 遷移金属ダイカルコゲナイドにおける非従来型電荷秩序の微視的理論

    山川洋一、平田徹、大成誠一郎、紺谷浩

    新学術領域研究「量子液晶の物性科学」量子物質開発フォーラム  2020.10.1 

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    Event date: 2020.10

    Language:English   Presentation type:Oral presentation (general)  

    Venue:online   Country:Japan  

  108. 一次元遷移金属テルル化物における超伝導

    東原直也, 吉川侑磨, 岡本佳比古, 山川洋一, 高津浩, 陰山洋, 竹中康司

    日本物理学会 2020年秋季大会  2020.9.11 

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    Event date: 2020.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:online   Country:Japan  

  109. 遷移金属ダイカルコゲナイド(TMD)における不整合CDWの発現機構

    平田徹, 山川洋一, 大成誠一郎, 紺谷浩

    日本物理学会 2020年秋季大会  2020.9.11 

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    Event date: 2020.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:online   Country:Japan  

  110. 銅酸化物びIr酸化物における新奇な奇パリティー液晶秩序の発現機構

    紺谷浩, 山川洋一, 田財里奈, 大成誠一郎

    日本物理学会 2020年秋季大会  2020.9.11 

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    Event date: 2020.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:online   Country:Japan  

  111. 汎関数くりこみ群を用いた量子液晶状態の研究

    田財里奈, 山川洋一, 土射津昌久, 紺谷浩

    日本物理学会 2020年秋季大会  2020.9.11 

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    Event date: 2020.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:online   Country:Japan  

  112. 拡張軌道揺らぎ由来の超伝導の理論研究:高ドープFeSeへの適用

    山川洋一, 大成誠一郎, 紺谷浩

    日本物理学会 2020年秋季大会  2020.9.11 

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    Event date: 2020.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:online   Country:Japan  

  113. 汎関数くりこみ群を用いた量子液晶状態の研究

    田財里奈, 山川洋一, 土射津昌久, 紺谷浩

    新学術領域研究「量子液晶の物性科学」 C01班公募研究キックオフミーティング  2020.7.9 

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    Event date: 2020.7

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:online   Country:Japan  

▼display all

KAKENHI (Grants-in-Aid for Scientific Research) 5

  1. Theoretical study of loop current order, nematic order, and superconductivity in strongly correlated electron systems

    Grant number:24K06938  2024.4 - 2028.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

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    Authorship:Principal investigator 

    Grant amount:\4550000 ( Direct Cost: \3500000 、 Indirect Cost:\1050000 )

  2. 強相関電子系における電子ネマティックと高温超伝導および擬ギャップの理論研究

    Grant number:20K03858  2020.4 - 2024.3

    日本学術振興会  科学研究費助成事業  基盤研究(C)

    山川 洋一

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    Authorship:Principal investigator  Grant type:Competitive

    Grant amount:\4290000 ( Direct Cost: \3300000 、 Indirect Cost:\990000 )

    近年、鉄系や銅酸化物高温超伝導体などの強相関電子系において、多様なネマティック現象が発見されている。電子ネマティック現象は異方性の獲得にとどまらず、高温超伝導や擬ギャップといった重要な未解決現象を解明するカギだが、その正体は明らかではない。本研究では、鉄系や銅酸化物、さらに関連物質として有機物超伝導体に着目する。現実的なハバード模型に基づいた微視的計算により、これらの物質における電子ネマティック現象を包括的に理解し、その揺らぎを媒介とした超伝導・擬ギャップの発現機構を解明する。
    2022年度は、近年発見され注目を集めているカゴメ格子超伝導体 AV3Sb5(A=Cs, Rb, K) に着目した。2次元の2次元カゴメ格子は強い幾何学的フラストレーションを持ち、従来は絶縁体においてスピン系の物理が議論されてきた。ところが2019年に発見されたAV3Sb5は金属であり、電荷秩序及び超伝導が生じる事が報告され、それらの起源やフラストレーションとの関連などに大きな注目が集待っている。本研究では、2次元ハバード模型に基づいて、高次の電子間相関を表すバーテックス補正を考慮して、その常伝導・超伝導状態を解析した。その結果、フラストレーションによりスピン秩序には至らず、スピン揺らぎが多重に散乱し干渉することで電子のサイト間の飛び移り積分が増減するボンド秩序が生じる事を見出した。このボンド秩序は、実験で観測されている電荷密度波転移と整合する。さらに、このボンド秩序に起因して超伝導の可能性として、異方的s波とp波の可能性を提唱した。さらに、非磁性不純物を加えるとフルギャップのs波超伝導状態に変化する事を明らかにした。フラストレーションという観点では、2次元三角格子持つ遷移金属ダイカルコゲナイド1T-TaS2について解析し、高温で観測される非整合電荷密度波の起源として、高次の多体電子相関に起因した電荷・軌道・ボンドの混合秩序状態を提案した。加えて、鉄系超伝導体の電子ドープFeSeにおいて、電子ドープによりネマティック状態が空間的に変調して整列する、電子スメクティック秩序に対する揺らぎが発達し、その近傍で高温超伝導状態が生じる事を見出した。
    本研究では、電子間の多体相関に起因して、電子系が自発的に異方性を獲得する様々な電子ネマティック現象と、その量子臨界点近傍で現れる非フェルミ液体や高温超伝導機構の解明を目指す。これまでの研究により、軌道、ボンド、自発ループ電流、スピン流など、様々なネマティック秩序が生じる事が、電子相関は局所クーロン相互作用という、ある意味で単純なハバード模型から理解できる事が明らかとなった。さらには、この多彩な電子ネマティック状態は、鉄系超伝導体のみならず、銅酸化物高温超伝導体、さらには古くから議論されてきた遷移金属ダイカルコゲナイドから、近年発見されたカゴメ格子超伝導体まで、様々な強相関電子系でみられる普遍的な秩序状態の一つである。本研究により、その根底には多体の電子相関、特にスピン揺らぎ間の干渉機構という、共通の物理がある事が明らかとなってきた。
    これまでの研究により、強相関電子系において、軌道、ボンド、自発ループ電流、スピン流など、様々なネマティック秩序が生じる事が明らかとなった。その起源は、バーテックス補正で記述される多体の電子相関、特にAslamazov-Larkin項によるスピン揺らぎ間の干渉である。これらのネマティックの揺らぎが発達した場合、その揺らぎを媒介とした強い電子間相互作用が期待できる。そこで今後の研究計画としては、これらの揺らぎに起因した様々な物理現象を解析する。ここで重要となるのが、電子とネマティック揺らぎ間の結合である。しかしながら、ハバード模型のハミルトニアンには電子とボンド揺らぎとの結合を直接表す項が無いため、従来のMigdal近似(電子フォノン相互作用では良い近似として知られる)を適応してしまうと、ボンド揺らぎ由来の相互作用がゼロになってしまう。これは、Migdal近似ではバーテックス補正が無視されるためである。この状況を克服するため、バーテックス補正を考慮した既約相互作用の無限級数和を直接計算するという新手法を開発し、Migdal近似を超えた多体相関を考慮し、かつ現象論的なパラメータ無しに相互作用を求める。ネマティック揺らぎ由来の相互作用の直接計算により、鉄系超伝導体・銅酸化物などにおける量子臨界点近傍での有効質量や電気抵抗の異常な振る舞いや、高温超伝導状態を議論する。

  3. 一次元ディラック電子系物質における巨大熱電応答と熱・電気エネルギー変換機能

    Grant number:20H02603  2020.4 - 2023.3

    日本学術振興会  科学研究費助成事業  基盤研究(B)

    岡本 佳比古, 山川 洋一, 山影 相

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    Authorship:Coinvestigator(s)  Grant type:Competitive

    Grant amount:\18070000 ( Direct Cost: \13900000 、 Indirect Cost:\4170000 )

    一次元ディラック電子系物質Ta4SiTe4の巨大熱電応答を活用することにより、革新的な高性能を示す熱電変換材料を開発する。本物質が室温以下で巨大なゼーベック係数を示すことにとって、一次元性の強い電子バンドがフェルミ準位で交差した「一次元ディラック電子系」と呼べる状況が重要と考えられるが、詳細は不明である。系統的に組成制御したバルク試料の合成、単結晶試料を用いた物性測定と理論構築、同様の状況を実現する新物質の開拓により、Bi2Te3系の実用材料と比べて高性能・低温動作可能な新材料を確立する。我々の身の回りの温度差を用いた環境発電や、これまで未踏の-100℃以下における局所冷却の実用化に貢献する。
    本年度は、一次元ディラック電子系の新物質開拓として、Ta4SiTe4と同じ結晶構造をもち、Siサイトを様々な遷移金属元素に置き換えた物質の合成を中心に取り組んだ。これまで、これらの物質の熱電変換性能に関する報告はない。その結果、十分に遷移金属元素が含まれるNb4(M, Si)Te4 (M = Cr, Fe, Co, Ni)のウィスカー結晶の合成に成功した。これらはいずれも、これまでに合成の報告のない新物質である。バルクサイズの試料合成はできなかったものの、得られたウィスカー結晶を用いて、各種の物性測定を行った。
    Nb4(M, Si)Te4ウィスカー結晶はいずれも、金属的な電気伝導を示した。熱起電力については、熱電変換材料として有望な大きな値は現状では得られていない。このうち、Nb4(Co, Si)Te4の磁気抵抗は、磁場に対して直線的に増加する特異な振る舞いを示した一方、Nb4(Cr, Si)Te4とNb4(Fe, Si)Te4では負の磁気抵抗が現れた。負の磁気抵抗は、局在スピンによる伝導電子の散乱が磁場印加によって抑制されたことにより現れたと考えられる。また、Nb4(Fe, Si)Te4の磁化率測定により、転移温度15 Kのスピングラス的な振る舞いを観測した。一般にスピングラスは、局在スピン間に働く磁気相互作用が一様でない場合に現れる。Nb4(Fe, Si)Te4では磁性を担うFeと非磁性のSiがランダムに並んだ一次元鎖が形成されていると予想され、このランダムネスがスピングラスの原因となっていると考えられる。
    本年度は、これらの物質以外についても、一次元ディラック電子系候補BaTiSe3の合成、反射率測定によるTa4SiTe4の電子状態評価、Ta4SiTe4関連物質であるTa2Pd3Te5、Nb2Pd3Te5、Ta3SiTe6の単結晶合成と物性測定についても行った。
    本研究の目標として、I. Ta4SiTe4系バルク試料の合成と熱電変換性能の最適化、II. 巨大熱電応答の発現機構解明、III. 一次元ディラック電子系の新物質開拓、の3点を計画した。このうち、Iについては、令和2年度にTa4SiTe4とNb4SiTe4の固溶体に対して、様々に元素置換した試料の合成に成功し、固溶体においてp型・n型の高い熱電変換特性を実現した。これは、本物質系を実用材料の候補とするために必要不可欠な過程の一つである。IIについては、令和2・3年度において、Ta4SiTe4の単結晶を用いて初めて反射率の測定を行った。それにより、一次元性が強く、非常に小さいバンドギャップをもつ電子状態に関する実験データを初めて得ることができた。IIIについては、新物質開拓の結果、Ta4SiTe4とよく似た特徴を示すTa2Pd3Te5とNb2Pd3Te5や、Ta4SiTe4と同じ結晶構造をもつNb4MTe4 (M = Cr, Co, Fe)を合成し、物性測定を行ってきた。また、令和3年度においては、新しい一次元ディラック電子系の候補物質であるBaTiSe3の単結晶合成にも取り組んだ。今後、これらの物質に対して様々に元素置換を行い、キャリア数やバンド幅を制御することにより、熱電特性の改善が期待される。
    令和4年度は、以下の研究計画I~IIIに関して、以下の計画に従って研究を遂行する。研究計画I. Ta4SiTe4系バルク試料の合成と熱電変換性能の最適化については、まず、これまでの研究において反射率測定を行えていないNb4SiTe4の大型単結晶の合成を行う。また、令和3年度において合成に成功したNb4(M, Si)Te4 (M = Cr, Fe, Co, Ni)ウィスカー結晶についても大型単結晶の合成に取り組む。研究計画II. 巨大熱電応答の発現機構解明については、Ta4SiTe4に加えて、Nb4SiTe4の反射率測定を行い、光学伝導度を評価する。両物質の電子状態についての実験データを比較し、系統的に解釈することで、本系が低温で高い熱電変換特性を示す機構の解明に繋げる。研究計画III. 一次元ディラック電子系の新物質開拓については、現在合成、物性測定を行っているTa2Pd3Te5、Nb2Pd3Te5、Nb4MTe4、BaTiSe3、Ta3SiTe6に加え、さらなる新物質開拓を行う。

  4. Theoretical study on the orbital and magnetic fluctuations on multi-orbital strongly-correlated electron systems

    Grant number:17K14338  2017.4 - 2021.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Young Scientists (B)

    Yamakawa Youichi

      More details

    Authorship:Principal investigator  Grant type:Competitive

    Grant amount:\4290000 ( Direct Cost: \3300000 、 Indirect Cost:\990000 )

    In this study, we investigated the electronic states in Fe-based and cuprate superconductors based on the higher-order many-body effect described by vertex corrections. As a result, we found that the orbital fluctuations are developed in electron-doped FeSe thanks to the interference between spin fluctuations. The high-temperature superconductivity appears due to the orbital fluctuations. Also, the pressure-induced magnetic transition in FeSe is well explained based on this study. We also showed that the resonance-like structure obtained by neutron scattering measurement is consistent with the s++ wave superconductivity due to orbital-fluctuations. In addition, we proposed the bond and spin-current orders as the origins of recently discovered charge-density wave and the pseud-gap nature in cuprate superconductors.

  5. Dirac electron system with Ca 3d electrons as a high performance thermoelectric material

    Grant number:16K13664  2016.4 - 2018.3

    Okamoto Yoshihiko

      More details

    Authorship:Coinvestigator(s)  Grant type:Competitive

    Grant amount:\3640000 ( Direct Cost: \2800000 、 Indirect Cost:\840000 )

    We studied thermoelectric properties of candidate Dirac electron systems with Ca 3d electrons, which are expected to show high thermoelectric performances. We prepared polycrystalline samples of antiperovskite oxide Ca3XO (X = Sn, Pb) and whisker crystals of one-dimensional Dirac electron system M4SiTe4 (M = Ta, Nb) and discovered that Ca3SnO and M4SiTe4 show high thermoelectric performances. Ternary Ca pnictides CaAgP and CaAgAs are found to be promising candidates to realize ideal line-node Dirac semimetals.

 

Teaching Experience (On-campus) 21

  1. Physics Tutorial IVb

    2023

     詳細を見る

    This tutorial course is a companion course to the Quantum Mechanics III lecture course. The two should be taken together.

    The purpose of this course is to cultivate students’ calculation skills and deepen their understanding of quantum mechanics -- i.e. Nature.

    This unit is the second half of a full-year course. Building on Quantum Mechanics II, students will learn quantum mechanics at an advanced undergraduate level. The course will build physical intuition of Nature on the quantum scale while improving students’ ability to express physical intuition in mathematical terms and to solve problems. Students will learn not to be overwhelmed by mathematical symbols, and to discern the simplicity of physical principles expressed by them.

    Quantum Mechanics III (together with this tutorial course) is an essential step towards higher level study in Condensed Matter Physics, High Energy Physics, Materials Science and many areas of Applied Physics. If taken together with Quantum Mechanics II, Statistical Physics II and Statistical Physics III, students will be well prepared to level up to Condensed Matter Field Theory and Quantum Field Theory in Year 4 or graduate study. Chemistry students have the opportunity to understand foundations of chemistry at a fundamental level and would gain an advantage over their peers.

    The main areas covered are:
    1. The connection between symmetries and conservation laws
    2. The Theory of Angular Momentum
    3. Spin and Paramagnetic Resonance
    4. The Variational Approach
    5. Perturbation Theory: Time Independent Nondegenerate; Time Independent Degenerate; Time Dependent
    6. Scattering Theory

  2. Physics Tutorial IVa

    2023

     詳細を見る

    This tutorial course is a companion course to the Statistical Physics III lecture course. The two should be taken together.

    The purpose of this course is to cultivate students’ calculation skills and deepen their understanding of statistical physics.

    Statistical Mechanics is one of the major fields of physics: around 30% of Physics Nobel Prizes have been awarded for discoveries directly or indirectly related to Statistical Mechanics, particularly phase transitions and field theories. The principles and methods are applicable in many fields of physics, including condensed matter physics (e.g. Bose Einstein Condensation, superconductivity, materials science) and high energy physics (spontaneous symmetry breaking, lattice gauge field theories, the Higgs Mechanism (which is a type of phase transition) and so on) as well as astrophysics (neutron stars, simulations of galaxy evolution, and so on). The principles and methods are also applicable in a very wide variety of fields outside physics, such as biology, neuroscience, modelling of pandemics, network theory, machine learning and artificial intelligence. G30 students in the past have shown that students in chemistry, chemical engineering and materials science with a thorough grounding in the principles of Statistical Mechanics have a significant advantage over their peers who do not possess this grounding.

    This is the second part of a full-year, intermediate-advanced Year 3 course in statistical mechanics and thermodynamics.

  3. Quantum Mechanics IV

    2023

  4. [G30] Core Condensed Matter Physics

    2023

     詳細を見る

    Each lecture is given by the individual professor shown in parentheses.
    Please note that the contents below are just tentative. The final program will be distributed at the first lecture.
    1. Introduction to Condensed Matter Physics III (Prof. Tomoyasu Taniyama)
    2. Theoretical Physics of Foods, Gels, Glasses, and All That (Prof. Kunimasa Miyazaki)
    3. Rheology of Soft Glassy Materials (Prof. Takeshi Kawasaki)
    4. Physics in Quasicrystals (Prof. Kazuhiko Deguchi)
    5. Condensed Matter Studies by NMR (Prof. Yoshiaki Kobayashi)
    6. Superconductivity and Exotic Electric States in Strongly Correlated Electron Systems (Prof. Hiroshi Kontani)
    7. Nematicity and Orbital Order (Prof. Seiichiro Onari)
    8. First Principles Calculation and its Application (Prof. Youichi Yamakawa)
    9. Quantum Liquids (Prof. Yasuhiro Shimizu)
    10. Massless Dirac Fermions in Condensed Matter Physics (Prof. Akito Kobayashi)
    11. Superfluidity (Prof. Taku Matsushita)
    12. Fundamentals and Applications of Ferroelectricity (Prof. Hiroki Taniguchi)
    13. The Uses of Spin : From Fundamentals to Spintronics (Prof. Hiroshi Kohno)
    14. Topological Material (Prof. Ai Yamakage)
    15. Nano-scale Magnetism (Prof. Tomoyasu Taniyama)

  5. Condensed Matter Physics III

    2023

     詳細を見る

    Each lecture is given by the individual professor shown in parentheses.
    Please note that the contents below are just tentative. The final program will be distributed at the first lecture.
    1. Introduction to Condensed Matter Physics III (Prof. Tomoyasu Taniyama)
    2. Theoretical Physics of Foods, Gels, Glasses, and All That (Prof. Kunimasa Miyazaki)
    3. Rheology of Soft Glassy Materials (Prof. Takeshi Kawasaki)
    4. Physics in Quasicrystals (Prof. Kazuhiko Deguchi)
    5. Condensed Matter Studies by NMR (Prof. Yoshiaki Kobayashi)
    6. Superconductivity and Exotic Electric States in Strongly Correlated Electron Systems (Prof. Hiroshi Kontani)
    7. Nematicity and Orbital Order (Prof. Seiichiro Onari)
    8. First Principles Calculation and its Application (Prof. Youichi Yamakawa)
    9. Quantum Liquids (Prof. Yasuhiro Shimizu)
    10. Massless Dirac Fermions in Condensed Matter Physics (Prof. Akito Kobayashi)
    11. Superfluidity (Prof. Taku Matsushita)
    12. Fundamentals and Applications of Ferroelectricity (Prof. Hiroki Taniguchi)
    13. The Uses of Spin : From Fundamentals to Spintronics (Prof. Hiroshi Kohno)
    14. Topological Material (Prof. Ai Yamakage)
    15. Nano-scale Magnetism (Prof. Tomoyasu Taniyama)

  6. Physics Tutorial I

    2022

  7. Physics Seminars I-I

    2022

  8. [G30] Core Condensed Matter Physics

    2022

     詳細を見る

    --- PURPOSE ---
    The purpose of this course is to show students cutting-edge research in condensed-matter physics and to motivate them to study this rich and fertile research area. This course also aims at reviewing fundamental physics such as electromagnetism, statistical physics, and quantum mechanics through various aspects of advanced materials. Each lecture is covered by a different professor, and the students can grasp various research frontiers throughout the course.

    --- Goal ---
    By the end of this course, students will be able to gain knowledge of recent trends in condensed-matter physics research and understand the essences of the topics given.

    --- Class content and structure ---
    Each lecture is given by the individual professor shown in parentheses.
    Please note that the contents below are just tentative. The final program will be distributed at the first lecture.
    1. Introduction to Condensed Matter Physics III (Prof. Tomoyasu Taniyama)
    2. Theoretical Physics of Foods, Gels, Glasses, and All That (Prof. Kunimasa Miyazaki)
    3. Rheology of Soft Glassy Materials (Prof. Takeshi Kawasaki)
    4. Physics in Quasicrystals (Prof. Kazuhiko Deguchi)
    5. Condensed Matter Studies by NMR (Prof. Yoshiaki Kobayashi)
    6. Superconductivity and Exotic Electric States in Strongly Correlated Electron Systems (Prof. Hiroshi Kontani)
    7. Nematicity and Orbital Order (Prof. Seiichiro Onari)
    8. First Principles Calculation and its Application (Prof. Youichi Yamakawa)
    9. Quantum Liquids (Prof. Yasuhiro Shimizu)
    10. Massless Dirac Fermions in Condensed Matter Physics (Prof. Akito Kobayashi)
    11. Superfluidity (Prof. Taku Matsushita)
    12. Fundamentals and Applications of Ferroelectricity (Prof. Hiroki Taniguchi)
    13. The Uses of Spin : From Fundamentals to Spintronics (Prof. Hiroshi Kohno)
    14. Topological Material (Prof. Ai Yamakage)
    15. Nano-scale Magnetism (Prof. Tomoyasu Taniyama)

  9. Condensed Matter Physics III

    2022

     詳細を見る

    --- PURPOSE ---
    The purpose of this course is to show students cutting-edge research in condensed-matter physics and to motivate them to study this rich and fertile research area. This course also aims at reviewing fundamental physics such as electromagnetism, statistical physics, and quantum mechanics through various aspects of advanced materials. Each lecture is covered by a different professor, and the students can grasp various research frontiers throughout the course.

    --- Goal ---
    By the end of this course, students will be able to gain knowledge of recent trends in condensed-matter physics research and understand the essences of the topics given.

    --- Class content and structure ---
    Each lecture is given by the individual professor shown in parentheses.
    Please note that the contents below are just tentative. The final program will be distributed at the first lecture.
    1. Introduction to Condensed Matter Physics III (Prof. Tomoyasu Taniyama)
    2. Theoretical Physics of Foods, Gels, Glasses, and All That (Prof. Kunimasa Miyazaki)
    3. Rheology of Soft Glassy Materials (Prof. Takeshi Kawasaki)
    4. Physics in Quasicrystals (Prof. Kazuhiko Deguchi)
    5. Condensed Matter Studies by NMR (Prof. Yoshiaki Kobayashi)
    6. Superconductivity and Exotic Electric States in Strongly Correlated Electron Systems (Prof. Hiroshi Kontani)
    7. Nematicity and Orbital Order (Prof. Seiichiro Onari)
    8. First Principles Calculation and its Application (Prof. Youichi Yamakawa)
    9. Quantum Liquids (Prof. Yasuhiro Shimizu)
    10. Massless Dirac Fermions in Condensed Matter Physics (Prof. Akito Kobayashi)
    11. Superfluidity (Prof. Taku Matsushita)
    12. Fundamentals and Applications of Ferroelectricity (Prof. Hiroki Taniguchi)
    13. The Uses of Spin : From Fundamentals to Spintronics (Prof. Hiroshi Kohno)
    14. Topological Material (Prof. Ai Yamakage)
    15. Nano-scale Magnetism (Prof. Tomoyasu Taniyama)

  10. Physics Tutorial I

    2021

  11. Physics Seminars I-I

    2021

  12. Physics Tutorial I

    2020

  13. Physics Seminars I-I

    2020

  14. 物理学演習Ⅲ

    2019

     詳細を見る

    ■本講義の目的とねらい
    講義の内容を理解し、さらに発展させるため少人数(約14名)形式の演習を行う。
    ■授業内容
    学生は6つのグループに分かれ、あらかじめ出題された統計物理及び量子力学の問題を解く。担当教員の指導、学生相互の討論により、基礎知識を充実し、深い思考力を涵養する。
    ■到達目標
    統計物理及び量子力学に対する理解を深める。
    ■成績評価の方法
    出席とレポート、発表、討論により評価。
    ■履修取り下げ制度および不可(F)と欠席の基準
    履修取り下げ制度を採用する。
    履修取り下げの場合は「欠席」とし、それ以外の成績不良者は「不合格」とする。
    ■その他
    日程表・クラス名簿は掲示で確認すること

  15. Physics Seminars I-I

    2019

  16. 物理学演習Ⅱ

    2018

     詳細を見る

    ■本講義の目的とねらい
    物理学の広い領域で必要とされる解析力学Ⅱ、電磁気学、量子力学Ⅰ及び統計物理学Ⅰの講義の内容をより深く理解し,具体的な物理の問題を解くための基礎知識の修得と思考力を育成することを目的とする。
    ■授業内容
    学生は4組に分かれ、各演習担当者の指導を受ける。講義担当者によって用意された練習問題について学生が回答を与え、議論し合うことによって授業を実施していく。具体的な実施方法は各組での話し合いによって決められる。
    ■到達目標
    基本的な演習問題を解く能力を身につける。
    ■成績評価の方法
    出席とレポート、発表により評価。
    ■履修取り下げ制度および不合格(F)と欠席の基準
    履修取り下げ制度を用いる。履修取り下げの場合は「欠席」とし、それ以外の成績不良者は「不合格」とする。
    ■その他 日程表・クラス名簿は掲示で確認すること。

  17. 物理学演習Ⅲ

    2018

     詳細を見る

    ■本講義の目的とねらい
    講義の内容を理解し、さらに発展させるため少人数(約14名)形式の演習を行う。
    ■授業内容
    学生は6つのグループに分かれ、あらかじめ出題された統計物理及び量子力学の問題を解く。担当教員の指導、学生相互の討論により、基礎知識を充実し、深い思考力を涵養する。
    ■到達目標
    統計物理及び量子力学に対する理解を深める。
    ■成績評価の方法
    出席とレポート、発表、討論により評価。
    ■履修取り下げ制度および不可(F)と欠席の基準
    履修取り下げ制度を採用する。
    履修取り下げの場合は「欠席」とし、それ以外の成績不良者は「不合格」とする。
    ■その他
    日程表・クラス名簿は掲示で確認すること

  18. 物理学演習Ⅲ

    2017

     詳細を見る

    ■本講義の目的とねらい
    講義の内容を理解し、さらに発展させるため少人数(約14名)形式の演習を行う。
    ■授業内容
    学生は6つのグループに分かれ、あらかじめ出題された統計物理及び量子力学の問題を解く。担当教員の指導、学生相互の討論により、基礎知識を充実し、深い思考力を涵養する。
    ■到達目標
    統計物理及び量子力学に対する理解を深める。
    ■成績評価の方法
    出席とレポート、発表、討論により評価。
    ■履修取り下げ制度および不可(F)と欠席の基準
    履修取り下げ制度を採用する。
    履修取り下げの場合は「欠席」とし、それ以外の成績不良者は「不合格」とする。
    ■その他
    日程表・クラス名簿は掲示で確認すること

  19. 物理学演習Ⅱ

    2017

     詳細を見る

    ■本講義の目的とねらい
    物理学の広い領域で必要とされる解析力学Ⅱ、電磁気学、量子力学Ⅰ及び統計物理学Ⅰの講義の内容をより深く理解し,具体的な物理の問題を解くための基礎知識の修得と思考力を育成することを目的とする。
    ■授業内容
    学生は4組に分かれ、各演習担当者の指導を受ける。講義担当者によって用意された練習問題について学生が回答を与え、議論し合うことによって授業を実施していく。具体的な実施方法は各組での話し合いによって決められる。
    ■到達目標
    基本的な演習問題を解く能力を身につける。
    ■成績評価の方法
    出席とレポート、発表により評価。
    ■履修取り下げ制度および不合格(F)と欠席の基準
    履修取り下げ制度を用いる。履修取り下げの場合は「欠席」とし、それ以外の成績不良者は「不合格」とする。
    ■その他 日程表・クラス名簿は掲示で確認すること。

  20. 物理学演習Ⅲ

    2016

     詳細を見る

    ■本講義の目的とねらい
    講義の内容を理解し、さらに発展させるため少人数(約14名)形式の演習を行う。
    ■授業内容
    学生は6つのグループに分かれ、あらかじめ出題された統計物理及び量子力学の問題を解く。担当教員の指導、学生相互の討論により、基礎知識を充実し、深い思考力を涵養する。
    ■到達目標
    統計物理及び量子力学に対する理解を深める。
    ■成績評価の方法
    出席とレポート、発表、討論により評価。
    ■履修取り下げ制度および不可(F)と欠席の基準
    履修取り下げ制度を採用する。
    履修取り下げの場合は「欠席」とし、それ以外の成績不良者は「不合格」とする。
    ■その他
    日程表・クラス名簿は掲示で確認すること

  21. 物理学演習Ⅱ

    2016

     詳細を見る

    ■本講義の目的とねらい
    物理学の広い領域で必要とされる解析力学Ⅱ、電磁気学、量子力学Ⅰ及び統計物理学Ⅰの講義の内容をより深く理解し,具体的な物理の問題を解くための基礎知識の修得と思考力を育成することを目的とする。
    ■授業内容
    学生は4組に分かれ、各演習担当者の指導を受ける。講義担当者によって用意された練習問題について学生が回答を与え、議論し合うことによって授業を実施していく。具体的な実施方法は各組での話し合いによって決められる。
    ■到達目標
    基本的な演習問題を解く能力を身につける。
    ■成績評価の方法
    出席とレポート、発表により評価。
    ■履修取り下げ制度および不合格(F)と欠席の基準
    履修取り下げ制度を用いる。履修取り下げの場合は「欠席」とし、それ以外の成績不良者は「不合格」とする。
    ■その他 日程表・クラス名簿は掲示で確認すること。

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Social Contribution 1

  1. 名古屋大学理学部および物理学研究の紹介

    Role(s):Lecturer

    愛知県立明和高等学校  2023.6