量子ホール・フェロマグネットの間の移行時に抵抗がピークする

E P De Poortere¹, E Tutuc, S J Papadakis

¹Department of Electrical Engineering, Princeton University, Princeton, NJ 08544, USA. poortere@ee.princeton.edu

Science (New York, N.Y.)

|November 25, 2000

まとめ

アルミニウムアルセニド量子井戸内の二次元電子系において,第一級磁気移行が観察されました. 抵抗のピークによって特徴づけられるこれらの移行は,磁域の消散と金属の鉄磁気性についての洞察を明らかにします.

科学分野:

凝縮物質物理学凝縮物質物理学
量子材料科学とは,量子材料科学である.

背景:

二次元電子システム (2DES) は,複雑な磁気行動を示します.
磁気移行の理解は,新しい電子機器の開発に不可欠です.

研究の目的:

2DES.における第1次磁気移行を調査する.
エネルギー消耗における磁気領域の役割を分析する.
磁気移行中の交換相関エネルギーの変化を測定する.

主な方法:

アルミニウムアルセニド (AlAs) の量子井戸の製造.
パラレルと垂直の磁場を組み合わせたサンプル抵抗の実験測定.
ヒステリック抵抗のスパイクの分析.

主要な成果:

AlAs 2DESで低キャリア密度で観測された第1次磁気移行.
異なる部分磁化状態の間の移行に対応するヒステリック抵抗のスパイクが特定されました.
磁気ドメインが,移行中のエネルギー分散を大幅に増加させることを実証した.
磁気移行における交換相関エネルギーの変化を定量化した.

結論:

この研究は,2DES.における第1次磁気移行を確認した.
発見は,磁気領域がフェロ磁気材料の分散に与える影響を強調しています.
結果は,交換相関エネルギーの探査方法を提供し,金属の鉄磁気力の理解を進めています.

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