ポジティブとネガティブの磁気流電効果は,Aサイトでオーダーされた (BiMn3) Mn4O12ペロブスキート (perovskite) で示される
Naoki Imamura1, Maarit Karppinen, Teruki Motohashi
1Materials and Structures Laboratory, Tokyo Institute of Technology, Yokohama 226-8503, Japan.
Journal of the American Chemical Society
|October 22, 2008
まとめ
研究者は,高圧方法を使用して,Aサイトオーダーペロブスキート (BiMn3) Mn4O12を合成しました. この材料は2つの磁気変遷と,温度と磁気状態によって変化する,調節可能な磁気流電効果を示した.
科学分野:
- 固体化学 固体化学
- 材料科学は材料科学である.
- マグネチズム (磁気) とは
背景:
- ペロブスキート材料は,多様な機能特性で知られています.
- ペロブスキットのA位点の順序は,磁気や介電の振る舞いに大きく影響する.
- 複雑な酸化物の構造と性質の関係を理解することは,新しい電子材料の開発に不可欠です.
研究 の 目的:
- 新しいA位点のオーダーペロブスキート, (BiMn3) Mn4O12.2を合成し,特徴づけること.
- 合成された材料の磁気特性と移行を調査する.
- 温度と磁気状態との関係で磁気流電反応を探求する.
主な方法:
- 高圧合成経路は5GPaで発生する.
- 磁気移行を特定するための磁気感受性測定.
- 様々な温度範囲と磁場における介電性測定.
主要な成果:
- Aサイトでオーダーされたペロブスキート (BiMn3) Mn4O12.2の合成が成功しました.
- 2つの異なる磁気移行の観測.
- 温度と磁気状態に依存する,陽性または負の磁気流電効果の実証.
結論:
- Aサイトでオーダーされたペロブスキート (BiMn3) Mn4O12は,複雑な磁気行動を示す.
- この材料は,切り替え可能な磁気流電効果を示し,調節可能な電子アプリケーションの可能性を強調しています.
- 高圧合成は,ユニークな性質を持つ新しいペロブスキート構造にアクセスするための効果的な経路です.
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