二重ペロブスキットCa2FeOsO6の格子歪みによって引き起こされる高温フェリ磁気性
Hai L Feng1, Masao Arai, Yoshitaka Matsushita
1Superconducting Properties Unit, National Institute for Materials Science , 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.
Journal of the American Chemical Society
|February 21, 2014
まとめ
研究者らは,高温フェルマグネティズムを示す新しい5d-3dハイブリッド酸化物,Ca2FeOsO6を合成した. この発見は,高度なスピントロニック材料への道を開く.
科学分野:
- 固体化学 固体化学
- マテリアルサイエンス 材料科学
- 凝縮物質物理学 凝縮物質物理学
背景:
- ダブルペロブスキート酸化物は,電子アプリケーションに有望である.
- ハイブリッド酸化物における構造-特性関係を理解することは,材料設計において極めて重要です.
- 高温磁気分離器は,スピントロニックデバイスに求められています.
研究 の 目的:
- 新型5d-3dハイブリッド固体酸化物Ca2FeOsO6.6を合成し,特徴づけること.
- その結晶構造,磁気特性,電子状態を調査する.
- その高温フェリー磁性の背後にあるメカニズムを探求する.
主な方法:
- 高圧,高温の合成技術. 高圧,高温の合成技術. 高圧,高温の合成技術. 高圧,高温の合成技術.
- 結晶学的分析のためのX線 difraktion.
- 磁気移行温度を決定するための磁気感受性測定.
- 電子構造の計算を電子状態を検知するために行う.
主要な成果:
- Ca2FeOsO6は,オーダーされた二重ペロブスキート構造 (空間群P21/n) で結晶化します.
- 約320K (Tc) で長距離フェリ磁気移行を示しています.
- 材料は電気的に絶縁性であり,その電子状態は半金属に近い.
- 高Tcフェリ磁性は,格子歪みと複雑なスピン軌道相互作用に起因し,ダブルペロブスキート酸化物における新しい観察である.
結論:
- 高Tcの5d-3dハイブリッドフェリマグネティック断熱器の新しいクラスが確立されました.
- この発見は,フェリ磁性を駆動する際の格子歪みとスピン軌道相互作用の重要な役割を強調しています.
- Ca2FeOsO6は,実用的で科学的に価値のあるスピントロニック材料の開発に有望な候補である.
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