在Kagome磁体中反铁磁和局部对称性破坏的同时发展 (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
概括
在Cosn中使用Fe会产生反铁磁秩序和局部对称性破坏. 这种磁性排序破坏了六角格子的稳定性, 揭示了磁性和kagome金属结构扭曲之间的联系.
科学领域:
- 凝聚物质物理学
- 材料科学
- 磁性
背景情况:
- 像CoSn和FeSn这样的Kagome晶格金属表现出平面电子带和独特的特性.
- 了解它们的物理行为通常仅限于分析平均晶体结构.
研究的目的:
- 研究Fe-doping对Cosn的影响,特别是磁性秩序和结构对称性的出现.
- 探索磁性排序与 (Co,Fe) Sn 的局部结构扭曲之间的关系.
主要方法:
- 雷特维尔德对中子和同步射线衍射数据的分析.
- 反向蒙特卡洛 (RMC) 模拟同步射线总散射数据.
主要成果:
- 在 (Co0.45Fe0.55) Sn 中确定了A型的抗铁磁顺序,磁矩垂直于kagome层.
- 在八面体扭曲和格子常数"c"中观察到的异常与磁顺序相关.
- 通过RMC建模捕获了局部形扭曲和离轴Sn(2) 位移.
- 证明反铁磁秩序诱导局部对称性破坏和格子不稳定性.
结论:
- 六角格子在反铁磁过渡温度下变得不稳定.
- 局部对称性破坏归因于磁源,特别是外平面磁交换合.
- 揭示了反铁磁秩序,八面体扭曲和隐藏的局部对称性破坏之间的合.
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