マンガニット薄膜の浸透を直接観察した
Liuwan Zhang1, Casey Israel, Amlan Biswas
1Department of Physics, University of Texas, Austin, TX 78712, USA.
Science (New York, N.Y.)
|September 21, 2002
まとめ
LaPrCaMnO3フィルムの鉄磁領域は,冷却時に成長するが,温暖化時に成長せず,抵抗力の変化を引き起こします. この磁気不均一性は,材料の磁気抵抗性特性を説明する.
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
- マグネティズム (磁気) とは
背景:
- La0.33Pr0.34Ca0.33MnO3は,複雑な磁気および電子特性を有しています.
- ドメインのダイナミクスを理解することは,ペロブスキートマンガニートの磁気抵抗を説明するために不可欠です.
研究 の 目的:
- La0.33Pr0.34Ca0.33MnO3薄膜におけるフェロ磁気ドメインの温度に依存する行動を調査する.
- ドメインの成長と磁気特性を,抵抗力変化と磁気抵抗と相関させるため.
主な方法:
- 金属・断熱器のトランジションにおける抵抗性の測定.
- 冷却と温暖化のサイクル中の磁域画像と分析.
主要な成果:
- フェロ磁気ドメインは,メタル・インソレーターの移行温度 (TP1) 以下の冷却時に成長し,加熱中にTP1.1に近いまで静止状態にとどまります.
- 平均磁化率の低下は,抵抗力の跳躍と相関する.
- 局所磁気ヒステリシスと不均一性が観察され,一部のドメインはTP2.0以上で持続する.
結論:
- 観測されたドメインのダイナミクスと磁気不均一性は,La0.33Pr0.34Ca0.33MnO3.3における磁気抵抗を理解するための鍵となるものです.
- 温暖化と冷却の間の非対称ドメインの成長は,抵抗性のヒステレスに寄与する.
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