ID | 62764 |
FullText URL | |
Author |
Miyajima, Mizuki
Department of Physics, Okayama University
Astuti, Fahmi
Advanced Meson Science Laboratory, RIKEN Nishina Center
Fukuda, Takahito
Department of Physics, Okayama University
Kodani, Masashi
Department of Physics, Okayama University
Iida, Shinsuke
Institute for Solid State Physics, University of Tokyo
Asai, Shinichiro
Institute for Solid State Physics, University of Tokyo
Matsuo, Akira
Institute for Solid State Physics, University of Tokyo
Masuda, Takatsugu
Institute for Solid State Physics, University of Tokyo
Kindo, Koichi
Institute for Solid State Physics, University of Tokyo
Hasegawa, Takumi
Graduate School of Advanced Science and Engineering, Hiroshima University
Nakano, Takehito
Institute of Quantum Beam Science, Ibaraki University
Watanabe, Isao
Advanced Meson Science Laboratory, RIKEN Nishina Center
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Abstract | We have investigated the low-temperature magnetism of sodium superoxide (NaO2), in which spin, orbital, and lattice degrees of freedom are closely entangled. The magnetic susceptibility shows anomalies at T1 = 220 K and T2 = 190 K, which correspond well to the structural phase transition temperatures, and a sudden decrease below T3 = 34 K. At 4.2 K, the magnetization shows a clear stepwise anomaly around 30 T with a large hysteresis. In addition, the muon spin relaxation experiments indicate no magnetic phase transition down to T = 0.3 K. The inelastic neutron scattering spectrum exhibits magnetic excitation with a finite energy gap. These results confirm that the ground state of NaO2 is a spin-singlet state. To understand this ground state in NaO2, we performed Raman scattering experiments. All the Raman-active libration modes expected for the marcasite phase below T2 are observed. Furthermore, we find that several new peaks appear below T3. This directly evidences the low crystal symmetry, namely, the presence of the phase transition at T3.We conclude that the singlet ground state of NaO2 is due to the spin-Peierls instability.
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Published Date | 2021-10-7
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Publication Title |
Physical Review B
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Volume | volume104
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Issue | issue14
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Publisher | American Physical Society (APS)
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Start Page | L140402
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ISSN | 2469-9950
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NCID | AA11187113
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Content Type |
Journal Article
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language |
English
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OAI-PMH Set |
岡山大学
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Copyright Holders | ©2021 American Physical Society
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File Version | publisher
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DOI | |
Web of Science KeyUT | |
Related Url | isVersionOf https://doi.org/10.1103/physrevb.104.l140402
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Citation | Mizuki Miyajima, Fahmi Astuti, Takahito Fukuda, Masashi Kodani, Shinsuke Iida, Shinichiro Asai, Akira Matsuo, Takatsugu Masuda, Koichi Kindo, Takumi Hasegawa, Tatsuo C. Kobayashi, Takehito Nakano, Isao Watanabe, and Takashi Kambe, Spin-gap formation due to spin-Peierls instability in π-orbital-ordered NaO2, Phys. Rev. B 104, L140402
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Funder Name |
High Energy Accelerator Research Organization
Japan Society for the Promotion of Science
Ministry of Education, Culture, Sports, Science and Technology
Photon Factory Program Advisory Committee
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助成番号 | 2019S01
20K20896
15H03529
21H04441
2017G636
2020G666
2019T003
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