Publications

2024

• Superconductivity in Hexagonal Zr₆CoAl₂-Type Zr₆RuBi₂ and Zr₆FeBi₂,
  Kosuke Yuchi*, Daisuke Nishio-Hamane, Keita Kojima, Kodai Moriyama, Ryutaro Okuma, and Yoshihiko Okamoto*,
  J. Phys. Soc. Jpn., accepted. (arXiv:2410.16684)
• Electronic Self-Organization in the β-Pyrochlore Oxide CsW₂O₆,
  Yoshihiko Okamoto*,
  J. Phys. Soc. Jpn. 93, 111006(1-16) (2024). (open access) (arXiv:2406.13981)
• Selective Synthesis and Crystal Chemistry of Candidate Rare-Earth Kitaev Materials: Honeycomb and Hyperhoneycomb Na₂PrO₃,
  Ryutaro Okuma*, Kylie MacFarquharson, and Radu Coldea,
  Inorg. Chem. 63, 15941-15950 (2024).
• Unbalanced Charge Distribution Stabilized by Orbital Ordering,
  Yoshihiko Okamoto*,
  JPSJ News and Comments 21, 13(1-2) (2024). (open access)
• Pseudo-One-Dimensional Ribbon Chain Cluster Realized under High Pressure in 1T−VSe₂,
  T. Hara, N. Katayama*, S. Kitou, K. Kojima, S. Kawaguchi, and H. Sawa,
  Phys. Rev. B 110, L020103(1-6) (2024).
• Electric Field-Induced Volume Change in Pyro-Vanadate-Phosphates: Toward an Alternative Actuator Architecture,
  K. Takada, J. Shibutani, K .Yagi, F. Ikawa, Y. Yokoyama, D. Hirai, Y. Okamoto, N. Katayama, Y. Uemura, L. M. G. H. Chavas, T. Hatano, A. Fujita, and K. Takenaka*,
  Appl. Phys. Lett. 125, 041903(1-6) (2024).
• Emergent Topological Magnetism in Hund's Excitonic Insulator,
  R. Okuma*, K. Yamagami*, Y. Fujisawa, C. H. Hsu, Y. Obata, N. Tomoda, M. Dronova, K. Kuroda, H. Ishikawa, K. Kawaguchi, K. Aido, K. Kindo, Y. H. Chan, H. Lin, Y. Ihara, T. Kondo, Y. Okada,
  submitted. (arXiv:2405.16781)
• Anisotropic Optical Conductivity Accompanied by a Small Energy Gap in One-Dimensional Thermoelectric Telluride Ta₄SiTe₄,
  Fumiya Matsunaga, Yoshihiko Okamoto*, Yasunori Yokoyama, Kanji Takehana, Yasutaka Imanaka, Yuto Nakamura, Hideo Kishida, Shoya Kawano, Kazuyuki Matsuhira, and Koshi Takenaka,
  Phys. Rev. B 109, L161105(1-6) (2024). (arXiv:2311.13031)
• Nonmagnetic Ground State in RuO₂ Revealed by Muon Spin Rotation,
  M. Hiraishi, H. Okabe, A. Koda, R. Kadono, T. Muroi, D. Hirai, and Z. Hiroi,
  Phys. Rev. Lett. 132, 166702(1-6) (2024).
• Superconductivity in Ternary Zirconium Telluride Zr₆MTe₂ with 3d Transition Metals,
  Haruka Matsumoto, Youichi Yamakawa, Ryutaro Okuma, Daisuke Nishio-Hamane, and Yoshihiko Okamoto*,
  J. Phys. Soc. Jpn. 93, 023705(1-5) (2024). (arXiv:2401.04870)
• Superconductivity in Ternary Germanide ScPdGe and Silicide ScPdSi,
  Yusaku Shinoda, Yoshihiko Okamoto*, Youichi Yamakawa, Hiroshi Takatsu, Hiroshi Kageyama, Daigorou Hirai, and Koshi Takenaka,
  J. Phys. Soc. Jpn. 93, 023701(1-4) (2024). (arXiv:2312.06045)

2023

• Electroactive Actuator Composites Using Volume Change Induced by Insulator-to-Metal Transition in VO₂,
  K. Takenaka*, Y. Mizuno, J. Shibutani, K. Kishida, K. Takada, K. Yagi, Y. Yokoyama, N. Katayama, Y. Okamoto, D. Hirai, T. Hatano, and A. Fujita,
  Appl. Phys. Lett. 123, 231905(1-6) (2023).
  (Featured Article)
• Evidence of Unconventional Superconductivity on the Surface of the Nodal Semimetal CaAg_1-xPd_xP,
  Rikizo Yano*, Shota Nagasaka, Naoki Matsubara, Kazushige Saigusa, Tsuyoshi Tanda, Seiichiro Ito, Ai Yamagake, Yoshihiko Okamoto*, Koshi Takenaka, and Satoshi Kashiwaya*,
  Nat. Commun. 14, 6817(1-6) (2023) (open access).
• Superconductivity in Ternary Scandium Telluride Sc₆MTe₂ with 3d, 4d, and 5d Transition Metals,
  Yusaku Shinoda, Yoshihiko Okamoto*, Youichi Yamakawa, Haruka Matsumoto, Daigorou Hirai, and Koshi Takenaka,
  J. Phys. Soc. Jpn. 92, 103701(1-5) (2023). (arXiv:2304.01444) (oprn access)
  (JPSJ Papers of Editors' Choice)
  (JPSJ Hot Topics: A New Superconductor Family with Various Magnetic Elements)
• Structural and Electronic Properties of a Triangular Lattice Magnet NaPrTe₂ Compared with NaNdTe₂ and NaTbTe₂,
  Koki Eto, Yoshihiko Okamoto*, Naoyuki Katayama, Hajime Ishikawa, Koichi Kindo, and Koshi Takenaka,
  J. Phys. Soc. Jpn. 92, 094707(1-6) (2023). (arXiv:2307.06516)
• Signatures of a Magnetic Superstructure Phase Induced by Ultrahigh Magnetic Fields in a Breathing Pyrochlore Antiferromagnet,
  Masaki Gen*, Akihiko Ikeda, Kazushi Aoyama, Harald O. Jeschke, Yuto Ishii, Hajime Ishikawa, Takeshi Yajima, Yoshihiko Okamoto, Xuguang Zhou, Daisuke Nakamura, Shojiro Takeyama, Koichi Kindo, Yasuhiro H. Matsuda, Yoshimitsu Kohama*,
  Proc. Natl. Acad. Sci. 120, e2302756120(1-7) (2023). (arXiv:2301.09509)
• Large Magnetic-Field-Induced Strains in Sintered Chromium Tellurides,
  Yuki Kubota, Yoshihiko Okamoto*, Tomoya Kanematsu, Takeshi Yajima, Daigorou Hirai, and Koshi Takenaka,
  Appl. Phys. Lett. 122, 042404(1-6) (2023). (arXiv:2211.13388)
  (News: Science Japan "Group led by The Institute for Solid State Physics at The University of Tokyo discovers new material that significantly expands when a magnetic field is applied: Shows promise for new actuators")
• Systematic Study on the Role of the Third Zn-Site Element in Zn_2-xMg_xP₂O₇ Showing Giant Negative Thermal Expansion,
  Ryota Kasugai, Yoshifumi Kadowaki, Yasunori Yokoyama, Naoyuki Katayama, Yoshihiko Okamoto, and Koshi Takenaka*,
  Mater. Trans. 64, 638-642 (2023).
• Two-Band Model and Point Contact Spectroscopy of Nodal-Line Semimetal CaAg_0.9Pd_0.1P,
  Naoki Matsubara*, Shota Nagasaka, Rikizo Yano, Kazushige Saigusa, Yusaku Shinoda, Yoshihiko Okamoto, Koshi Takenaka, and Satoshi Kashiwaya,
  JPS Conf. Proc. 38, 011028(1-6) (2023).

2022

• Electronic Properties of Pyrochlore-Type Ca₂Ir₂O₇,
  Yuki Nakayama, Yoshihiko Okamoto*, Daigorou Hirai, and Koshi Takenaka,
  J. Phys. Soc. Jpn., 91, 125002(1-2) (2022). (arXiv:2211.09290)
• Electronic Structure Reconstruction by Trimer Formation in CsW₂O₆ Studied by X-Ray Photoelectron Spectroscopy,
  R. Nakamura, D. Takegami, A. Melendez-Sans, L. H. Tjeng, M. Okawa, T. Miyashino, N. L. Saini, M. Kitamura, D. Shiga, H. Kumigashira, M. Yoshimura, K.-D. Tsuei, Y. Okamoto, and T. Mizokawa,
  Phys. Rev. B, 106, 195104(1-6) (2022).
• Electrical-Field-Induced Insulator-to-Metal Transition in Samarium Monosulfides,
  K. Kishida, J. Shibutani, T. Hatano, Y. Yokoyama, N. Katayama, Y. Okamoto, Y. Nakamura, H. Kishida, H. S. Suzuki, K. Takehana, Y. Imanaka, and K. Takenaka*,
  Appl. Phys. Lett. 121, 121901(1-6) (2022).
• Complex Magnetic Phase Diagram with a Small Phase Pocket in a Three-Dimensional Frustrated Magnet CuInCr₄S₈,
  M. Gen*, H. Ishikawa, A. Ikeda, A. Miyake, Z. Yang, Y. Okamoto, M. Mori, K. Takenaka, T. Kurumaji, Y. Tokunaga, T. Arima, M. Tokunaga, K. Kindo, Y. H. Matsuda, Y. Kohama,
  Phys. Rev. Research 4, 033148(1-13) (2022). (arXiv:2112.08990)

• Publications before Mar. 2022 (Okamoto)