反鉄磁気トンネル交差点における八極駆動磁気抵抗
Xianzhe Chen1,2, Tomoya Higo1,2,3, Katsuhiro Tanaka4
1Department of Physics, University of Tokyo, Tokyo, Japan.
Nature
|January 18, 2023
まとめ
研究者らは,完全に反鉄磁気トンネルの交差点で有意なトンネリング磁気抵抗 (TMR) を観測した. この突破は,キラル反鉄磁石を用いて, 先進的なスピントロニクス装置への道を切り開いた.
科学分野:
- スピントロニクス
- 凝縮物質物理学
- 材料科学
背景:
- トンネリング磁気抵抗 (TMR) は,通常フェロマグネットで研究されるスピントロニクス装置にとって極めて重要です.
- TMRは,磁気トンネル結合 (MTJ) のフェロ磁気電極の相対磁化に依存する.
研究 の 目的:
- 完全に反鉄磁気トンネル交差点 (Mn3Sn/MgO/Mn3Sn) でTMRを調査する.
- スピントロニックの応用における反鉄磁性材料の可能性を調査する.
主な方法:
- Mn3Sn/MgO/Mn3SnとFe/MgO/Mn3Snの磁気トンネル接続の製造と測定について
- TMR比とスピン偏流の実験的特徴.
- チラルの反鉄磁石におけるTMRメカニズムの理論分析.
主要な成果:
- 室温で全抗フェロ磁性MTJで約2%のTMR比を観測する.
- オクトポール方向を操作することによって,アニゾトロプ的縦旋偏流方向に対する制御の実証.
- 測定されたTMR比は,観測されたスピン極化に基づく理論的推定を大幅に上回る.
結論:
- チラルの反鉄磁性MTJは,独特の極化特性により,実質的なTMRを示すことができます.
- この研究は,反鉄磁石を用いた超高速で効率的なスピントロニック装置の開発のための基盤を確立します.
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