多機能半導体スピントロニクス用のコヒーレントスピンの継続的な調達
I Malajovich1, J J Berry, N Samarth
1Department of Physics, University of California, Santa Barbara 93106, USA.
Nature
|July 19, 2001
まとめ
研究者らは,バイアス型半導体ヘテロ構造における持続スピン伝導モードを発見し,スピン伝送期間を大幅に延長しました. この突破は,電気または磁場制御を備えた高度なスピントロニックデバイスの見通しを高めています.
科学分野:
- 凝縮物質物理学 凝縮物質物理学
- 材料科学 材料科学とは
- 量子エレクトロニクス 量子エレクトロニクス
背景:
- 半導体はスピンコヒーレントトランスポートを示しており,これはスピントロニクスにとって極めて重要です.
- 半導体へのスピン注入は困難であり,しばしば磁性半導体に依存しています.
- 以前の光学方法では,インターフェースの間のスピン転送期間が短かった.
研究 の 目的:
- バイアス半導体ヘテロ構造における"持続的な"スピン伝導モードを調査する.
- 半導体インターフェースの間の一貫したスピン転送を強化する.
- スピントロニックデバイスの開発のための新しい道を探求する.
主な方法:
- バイアス型半導体ヘテロ構造を用いた.
- 時間解像度ケール光譜を用いた.
- パラレルチャネル経由のスピンコヒーレント注入を調査した.
主要な成果:
- 持続的なスピン伝導モードが非バイアス構造よりもずっと長く持続することを実証した.
- バイアス構造におけるスピンコヒーレントインジェクションの最大500%の増加が観察されました.
- 組み込みバイアスのためのp-nジャンクションで最大4000%の増加を達成しました.
結論:
- バイアス半導体ヘテロ構造は,継続的なスピンコヒーレント輸送を可能にします.
- この方法は,既存のスピンインジェクション技術よりも大幅に改善しています.
- 電気または磁場によって制御される多機能スピントロニックデバイスの道を開く.
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