Fe-ドーピングによるMnNiGe化合物の明確なスピン構造と巨大な気磁気効果
Feiran Shen1,2, Houbo Zhou1,2, Fengxia Hu1,2,3
1Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
Journal of the American Chemical Society
|May 3, 2021
まとめ
Fe-doped MnFeNiGeで新しい反鉄磁性スピン構造を発見しました それは圧力の下で鉄磁性状態に変化します この圧力誘発のスピン進化は,センサアプリケーションに有望な重要な気圧磁気効果を示しています.
科学分野:
- 材料科学
- 凝縮物質物理学
- マグネティズム
背景:
- 磁気システムのスピン構造は,競合する交換結合から生じる.
- 圧力は原子間距離と電子構造を変化させ,スピン進化と気磁気効果 (BME) を引き起こします.
- BMEはセンサーとアクチュエータに潜在的応用がある.
研究 の 目的:
- Fe-doped Mn0.87Fe0.13NiGeで新しいスピン構造を報告する.
- 圧力を駆動するスピン構造の進化とその関連する気磁気効果を調査する.
- 観測された現象を理論的に裏付ける.
主な方法:
- ニュートロン粉の difraktion (NPD) in situ 水位圧と磁場の下で.
- 最初の原則は 計算です
主要な成果:
- Fe-ドーピングされたMn0.87Fe0.13NiGeで新しいサイクロイドのスパイラル反鉄磁性 (CyS-AFMb) スピン構造が特定されました.
- 4kbar以上の圧力は,45°-CoS-FMaのコンフィギュレーションに変換する.
- この変換により,磁気モメントが短縮され (22%),BMEが強化された.
- 最初の原理の計算は,圧力誘発のスピン構造の進化と,Mn (Fe) 原子の3D帯域幅の拡大を支持した.
結論:
- この研究は,Fe-ドーピングされたMnFeNiGeにおける圧力の誘発による新しいスピン構造の進化を明らかにした.
- 観測された強化された気磁気効果は,高度な磁気センサーとアクチュエータの開発に重大な影響を及ぼします.
- 理論的な計算は,強化されたBMEとスピン構造の変換の背後にあるメカニズムを確認します.
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