LaFeO3-LaCrO3の超格子における鉄磁気性について
1The Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567, Japan.
Science (New York, N.Y.)
|May 22, 1998
まとめ
フェロマグネティック・スピン・オーダーは,LaCrO3-LaFeO3のスーパーラットで達成されました. Fe3+とCr3+イオンの人工的層付けにより,鉄磁気結合が可能になり,Fe-O-Cr材料における以前の課題を克服しました.
科学分野:
- 材料科学 材料科学とは
- 凝縮物質物理学 凝縮物質物理学
- 固体化学 固体化学
背景:
- Fe3+とCr3+イオンの間の酸素による鉄磁気結合は,確立された理論 (アンダーソン,グーデノフ,カナモリ法則) によって予測されています.
- Fe-O-Cr化合物に関する以前の研究は,ランダムなイオン分布によって妨げられ,鉄磁性の観察が妨げられました.
研究 の 目的:
- LaCrO3-LaFeO3の超格子でフェロマグネティック・スピン・オーダーを達成するために.
- Fe-O-Crシステムにおけるランダムなイオン配置の限界を克服するために.
主な方法:
- Fe3+およびCr3+イオンを精密に層に分け,人工的なスーパーラットスの製造.
- [111] 結晶学的な方向に沿った超格子の成長.
主要な成果:
- エンジニアリングされたLaCrO3-LaFeO3スーパーラットでフェロマグネティック・スピン・オーダーの実現.
- 制御されたレイヤリングがランダムイオン分布の問題を克服することを実証.
結論:
- 人工的な超グリットは,Fe-O-Crシステムで予測された鉄磁気結合を達成するための実行可能な経路を提供します.
- [111]層の超格子構造は,これらの材料の鉄磁性を観察する鍵です.
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