超伝導点接触点で金属のスピン偏振を測定する
1R. J. Soulen Jr., M. S. Osofsky, B. Nadgorny, T. Ambrose, S. F. Cheng, P. R. Broussard, Materials Physics, Naval Research Laboratory, Washington, DC 20375, USA. J. M. Byers, Department of Physics, George Washington University, Washington, DC 2.
Science (New York, N.Y.)
|October 2, 1998
まとめ
超伝導点コンタクトは,アンドレエフ反射を通して金属のスピン偏振を測定します. この方法により,様々な磁気材料のスピン極化が35~90%であることが明らかになる.
科学分野:
- 凝縮物質物理学 凝縮物質物理学
- マテリアルサイエンス 材料科学
- 量子力学は,量子力学という
背景:
- 超伝導点コンタクトは,電子特性を探すユニークな探査機を提供します.
- 超伝導体と金属の界面におけるアンドレエフ反射は,スピン依存型輸送に敏感である.
- スピン・ポラライゼーションの理解は,スピントロニック・アプリケーションにとって極めて重要です.
研究 の 目的:
- 様々な金属のフェルミエネルギーでのスピン偏振を決定する.
- スピン極化測定のための超伝導点コンタクトの有用性を実証する.
主な方法:
- 超伝導点コンタクトを使用して,異なる金属サンプルとのインターフェースを形成しました.
- 接触点の差伝導性を測定しました.
- アンドリーエフ反射原理に基づいてスピン偏分を推論するために,伝導率の変動を分析した.
主要な成果:
- Ni0.8Fe0.2,Ni,Co,Fe,NiMnSb,La0.7Sr0.3MnO3,およびCrO2.2を含むいくつかの金属のスピン偏振を成功裏に測定しました.
- 35%から90%までの幅広いスピン極化値が観察されました.
結論:
- 超伝導点接触スペクトロスコピーは,金属のスピン偏振を定量化するための効果的な技術です.
- この結果は,技術的に重要な磁気材料のスピン特性に関する貴重なデータを提供します.
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