マグネティズムとトポロジーの相互作用:アンチフェロマグネティックトポロジック断熱器における大きなトポロジックホール効果,EuCuAs
Subhajit Roychowdhury1, Kartik Samanta1, Premakumar Yanda1
1Max Planck Institute for Chemical Physics of Solids, 01187 Dresden, Germany.
Journal of the American Chemical Society
|June 2, 2023
まとめ
研究者らは,反鉄磁気物質のEuCuAsで大きなトポロジカルホール効果を発見し,以前の記録を超えました. この発見は複雑な磁気構造を用いた 新種のスピントロニック装置の扉を開くのです
科学分野:
- 凝縮物質物理学
- 材料科学
- マグネティズム
背景:
- 磁気相互作用と非平凡な帯構造は,異常なホール効果とトポロジカルホール効果 (THE) のようなエキゾチックな物理的性質をもたらします.
- 抗鉄磁性 (AFM) 材料は,その非日常的なスピン構造のためにTHEを示すことが知られている.
研究 の 目的:
- EuCuAsの磁気特性とトポロジックホール効果を調査する.
- スピントロニックの応用における EuCuAs の可能性を探求する.
主な方法:
- スピンの構造を決定するために,ニュートロン difraktion 実験が使用されました.
- トポロジカルホール抵抗性を観測するために磁気測定を行った.
主要な成果:
- EuCuAsは13Kで約7.4μΩ-cmのトポロジカルホール抵抗性を示し,Gd2PdSi3の抵抗性を上回る.
- ニュートロン difraktionは,大きなTHEの責任である,メタ磁性移行中に横断円のスピン構造を明らかにしました.
- 外部磁場は磁気順序を制御するために使用され,ディラックとウェイル半金属状態を明らかにした.
結論:
- EuCuAsは,独特の横断円のスピン構造によって導かれる重要なトポロジカルホール効果を示しています.
- EuCuAのトポロジカル状態を調整する能力は,高度なスピントロニックデバイスの可能性を示唆しています.
- 反鉄磁石の非平面的なスピン構成を調整することは,将来のスピントロニックアプリケーションにとって有望な経路を提供します.
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