Novel thermoelectric transport properties in chiral magnetic metals

2023 Fiscal Year Final Research Report

• Project/Area Number: 22K20360
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0202:Condensed matter physics, plasma science, nuclear engineering, earth resources engineering, energy engineering, and related fields
• Research Institution: Tokyo University of Science
• Principal Investigator: Sato Yoshiki 東京理科大学, 創域理工学部先端物理学科, 助教 (30962550)
• Project Period (FY): 2022-08-31 – 2024-03-31
• Keywords: キラル化合物 / 熱電物質 / フェルミ面 / 横熱電変換 / 単結晶育成

Outline of Final Research Achievements

The present study focuses on the peculiar magnetism and energy band structure in materials with chiral crystal structures, as well as the electronic transport phenomena arising from them. We reported the discovery of a new material GdPt2B and succeeded in growing single crystals of GdPt2B. In addition, we observed an anomalous Hall effect, which occurs by a non-trivial mechanism in GdPt2B, which exhibits characteristic magnetism due to the chirality of the crystal. Interesting results were also obtained in non-magnetic chiral crystals, such as the topology of the Fermi surface and characteristic thermoelectric transport phenomena in NbGe2 with strong electron-phonon interactions, and the axis-dependent conduction polarity in the chiral metal LaPt2B due to the mixed-dimensionality of the Fermi surfaces.

Free Research Field

物性物理学

Academic Significance and Societal Importance of the Research Achievements

持続可能な社会の実現のため、省エネルギーなメモリデバイスや、高効率な廃エネルギーの利用を可能にする熱電素子など、新しい機能性材料にかかる期待は大きい。キラル結晶は上述したような材料を探索する上で非常に有望なプラットフォームであり、また同時に、基礎学理を探求する上でも興味深い物質群である。本研究で報告した新しいキラル化合物や、そこで観測された異常な輸送現象や熱電変換は、基礎・応用の両方の観点から興味深い研究成果である。