フッ素化六角ペロフスキートにおける前例のない強力な反鉄磁性
Mihai Sturza1, Houria Kabbour, Sylvie Daviero-Minaud
1Université Lille Nord de France, UCCS, CNRS UMR 8181, ENSCL-USTL, Villeneuve d'Ascq, France.
Journal of the American Chemical Society
|June 9, 2011
まとめ
フッ素を六角ペロフスキットに導入すると,反鉄磁性 (AFM) オーダーリングが著しく強化されます. 700K近くに達するこの強化は,スピントロニクスアプリケーションのための堅牢なAFM材料の開発に不可欠です.
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
- マグネチズム (磁気) とは
背景:
- 高ニール温度を持つ反鉄磁性 (AFM) オキシドは,交換バイアスとマルチフェロイクを含むスピントロニクスにとって不可欠です.
- 六角ペロブスキート (HP) は,角を共有する構造と比較して,顔を共有する八面体により,典型的には弱い磁力交換を示します.
研究 の 目的:
- 鉄基六角ペロブスキート (HP) の部分的なフッ素 (F-) 置換の効果を調査する.
- これらの材料の反鉄磁気順序とネール温度 (T(N)) を強化し,潜在的なスピントロニックアプリケーションのために.
主な方法:
- フッ素代用鉄基六角ペロブスキートの実験合成と特徴付け.
- Ab initio計算は,実験的発見を裏付け,その背後にあるメカニズムを明らかにします.
主要な成果:
- FeベースのHPにF-を部分的に導入すると,反鉄磁性オーダリングが著しく増加します.
- 達成されたネール温度 (T(N)) は,約≈700Kであり,酸化鉄で報告されている最高値の1つです.
- フッ素の置換は,構造的変化と化学的還元をFe(3+) に誘導し,磁気交換を強化します.
結論:
- 有望なアニオン部位におけるO−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
- この研究は,先進技術のための高性能反鉄磁性材料を設計するための実行可能な戦略を示しています.
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