マグノン介質のスピントルクによる磁気化切り替え,反鉄磁気分離器を通過
Yi Wang1,2, Dapeng Zhu1, Yumeng Yang1
1Department of Electrical and Computer Engineering, National University of Singapore, 117576, Singapore.
Science (New York, N.Y.)
|November 30, 2019
まとめ
研究者は,マグノン電流を用いたエネルギー効率の良い磁気スイッチングを実証し,スピントロニックデバイスの電子ベースのスピン転送トルクに有望な代替案を提供した.
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:
- 地元の磁気化の効率的な操作は,磁気装置にとって極めて重要です.
- 電気回転移転トルク (STT) は一般的な方法ですが,ジョウルの加熱による高いエネルギー分散に苦しんでいます.
- 磁気化制御のためのエネルギー効率の良い代替品の開発は,活発な研究分野です.
研究 の 目的:
- マグノン電流を用いた磁気化スイッチングの代替アプローチを実験的に実証する.
- 室温でマグノン・トルク誘発磁気化の実現可能性を調査する.
- マグノン電流がスピン・モメンタル・モメントを 伝達する効率を評価する.
主な方法:
- Bi2Se3/反鉄磁気分離体 NiO/鉄磁気ヘテロ構造の製造
- マグノン電流を使って スピンの移転を誘導する
- マグノンのトルクによる磁気化スイッチの実験的な実証.
主要な成果:
- 室温でBi2Se3/NiO/フェロマグネット装置でマグノントルク誘導磁化スイッチを達成した.
- マグノン電流は,電子の関与なしに25nmのNiO層を通してスピン角運動量を効率的に運びました.
- マグノンのトルク効率は,以前に報告された電気回転トルク比と比較できる.
結論:
- マグノン電流は電磁化の制御のためのエネルギー効率の良いメカニズムを提供し,電気STTの限界を克服します.
- この研究は,高度な低分散型スピントロニックメモリとロジックデバイスの開発に道を開きます.
- この発見は,マグノンベースのスピントロニクスとデバイスアプリケーションの分野を活性化します.
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