多結晶カゴメ・フェロマグネットGdCo2における巨大な横断輸送特性と複雑なスピン構成の共存
Chaoxin Qiu1,2,3, Xiaolian Liu4, Cong Xiao1,2
1Jiangxi Provincial Key Laboratory of Magnetic Metallic Materials and Devices/Ganzhou Key Laboratory for Rare Earth Magnetic Functional Materials and Physics, Jiangxi University of Science and Technology, Ganzhou, 341000, China.
Small (Weinheim an der Bergstrasse, Germany)
|August 30, 2025
まとめ
この研究は,カゴメの格子フェロマグネットであるGdCo2が巨大な異常ホール伝導性と大きな異常ネルスト効果を示しています. これらの発見は,ユニークなスピン構造により,高度な熱電学およびスピントロニックの応用の可能性を強調しています.
科学分野:
- 凝縮物質物理学
- 材料科学
- スピントロニクス
- 熱電機
背景:
- カゴメの格子磁石は,その独特の横断輸送特性により,重要な関心があります.
- これらの性質は,熱電学およびスピントロニクスアプリケーションにとって不可欠なトポロジーと磁性の相互作用から生じる.
研究 の 目的:
- ポリクリスタルのカゴメ・フェロマグネットGdCo2の磁気,電気,熱電気輸送特性を徹底的に調査する.
- 複雑なスピン構成と観測された輸送現象との相関性を探求する.
主な方法:
- 磁気,電気,熱電気輸送特性の実験的特徴付け
- スキルミオンバブルや渦のような磁気構造の観測を含む複雑なスピン構成の分析
- 異常なホール伝導性,異常なネルスト効果,およびトポロジックホール効果の測定.
主要な成果:
- 巨大な異常ホール伝導度 (σyxA ≈ 2125 S cm−1) が10 Kで観察され,外的な歪み散布に起因した.
- 大きな異常なネルスト効果で,ネルスト係数 (SyxA ≈ 3.5 μV K−1) と横断熱伝導性 (αyxA ≈ 3.2 A m−1 K−1) があり,典型的なカゴメ磁石を上回っている.
- 安定した自発的なスキルミオンバブルと渦の証拠は,M形磁気抵抗行動と相関しています.
結論:
- GdCo2は巨大な横断輸送効果と複雑なスピン構造の驚くべき組み合わせを示しています.
- トポロジカルなホール・アンド・ネルスト効果を含む観測された現象は,非平凡なスピン構造の出現を確認している.
- GdCo2は,カゴメ磁石の横断輸送現象と基本的な物理学の探索に有望な材料です.
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