カゴメ磁石における反鉄磁気と局所対称性の同時発生 (Co0.45Fe0.55Sn)
Tsung-Han Yang1, Shang Gao2, Yuanpeng Zhang1
1Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States.
Journal of the American Chemical Society
|December 4, 2024
まとめ
CoSnにフェロドーピングは反鉄磁気秩序と局所的な対称性の破損を生じます. この磁気配列は六角格子を不安定化し 磁気とカゴメの構造的な歪みとの関係を明らかにします
科学分野:
- 凝縮物質物理学
- 材料科学
- マグネティズム
背景:
- CoSnやFeSnのようなカゴメ・グリッドの金属は,平らな電子帯とユニークな特性を表しています.
- 平均的な結晶構造の分析によって 物理的な振る舞いを理解することがしばしば制限されます
研究 の 目的:
- Fe-ドーピングがCosnに及ぼす影響,特に磁気秩序と構造的対称性の出現を調査する.
- (Co,Fe) Snにおける磁気順序と局所構造的歪みとの関係を調査する.
主な方法:
- ニュートロンとシンクロトロンX線微分データのリートヴェルド分析.
- シンクロトロンX線全分散データの逆モンテカルロ (RMC) モデリング.
主要な成果:
- カゴーム層に垂直な磁気モーメントを持つ, (Co0.45Fe0.55) Snで識別されたA型反鉄磁気順序.
- マグネティック・オーダーと相関する八面形の歪みと格子定数"c"の異常を観測した.
- RMCモデリングを使用して,局所オーソロンビック歪みとオフアシスSn(2) 位移を捕捉した.
- 抗鉄磁気秩序が局所的な対称性破裂と格子不安定性を誘発することを示した.
結論:
- 六角格子は反鉄磁気移行温度を下回ると不安定になります.
- 局所的な対称性破裂は磁気起源,特に平面外磁気交換カップリングに起因する.
- アンチ・フェロマグネティック・オーダーと 八面形の歪みと 隠された局所的な対称性破裂の 結合を明らかにした
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