磁気トンネル交差点のスピン偏振の決定における金属酸化物界面の役割
De Teresa JM1, Barthelemy, Fert
1Unite Mixte de Physique, CNRS-Thomson CSF, Laboratoire Central de Recherche, Domaine de Corbeville, 91404 Orsay, France, and Universite Paris-Sud, 91405 Orsay, France.
Science (New York, N.Y.)
|October 16, 1999
まとめ
金属酸化物インターフェイスは,磁気トンネル交差点における電子スピン極化に大きく影響します. インターフェースの結合効果は,スピン偏分を変化させ,磁気抵抗を強化する新しい方法を提供します.
科学分野:
- マテリアルサイエンス 材料科学
- 凝縮物質物理学 凝縮物質物理学
- 表面科学とは,地表科学である.
背景:
- マグネティック・トンネル・ジャンクション (MTJ) は,スピントロニック・デバイスにとって極めて重要です.
- フェロ磁性金属酸化物インターフェイスにおける電子スピン偏振を理解することは,デバイスの性能の鍵です.
研究 の 目的:
- 電子スピン偏振の決定における金属酸化物界面の役割を調査する.
- 異なるバリア材料がコバルトのスピン極化にどのように影響するかを調査する.
主な方法:
- 異なる金属酸化物インターフェースを持つ磁気トンネル交差点の製造と特徴付け.
- トンネリング光譜を用いた電子スピン偏振の測定.
主要な成果:
- コバルトは,アルミニウムバリアで正のスピン極化を示します.
- コバルトのスピン偏化は,ストロンチウムチタナートまたはセリウムランタナイトの障壁で負になります.
- 結果は,移行金属・バリアインターフェースの特定の結合効果に起因する.
結論:
- 金属酸化物インターフェースの電子構造は,スピン極化に根本的に影響する.
- テーラーリングインタフェース・ボンドは,MTJにおける磁気抵抗を最適化するための経路を提供します.
- この研究は,高度なスピントロニックデバイスの設計のための新しい道を開きます.
関連する概念動画
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