在高反铁磁磁体中,具有无序自旋方向的远程磁性秩序
Yao Shen1,2, Guangkai Zhang3,4, Qinghua Zhang3
1Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China. yshen@iphy.ac.cn.
Nature communications
|March 6, 2026
概括
具有原子混乱的高材料可以表现出远程磁性秩序. 这项研究揭示了 (MnFeCoNi) PS3 统一磁过渡中的独特旋转方向,挑战了传统的混乱-秩序关系.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 磁力学 磁力学 是一种
背景情况:
- 磁系统中的混乱通常会抑制远程秩序,有利于像旋转眼镜这样的短程状态.
- 高性材料,随着它们的随机原子排列,经常表现出复杂的磁性行为.
- 在无序系统中理解磁性秩序持久性和元素特异性行为是具有挑战性的.
研究的目的:
- 为了研究高的蜂晶格材料 (Mn1/4Fe1/4Co1/4Ni1/4) 的元素特异性磁顺序PS3.3.
- 在存在显著的原子混乱的情况下,阐明远程磁性秩序背后的机制.
- 探索单离子异构和交换相互作用之间的相互作用,以确定旋转方向.
主要方法:
- 使用中子衍射来确定整体磁性结构.
- 响应软X射线散射提供了元素特定的洞察力,对磁性秩序.
- 对衍射和散射数据的综合分析揭示了详细的磁性特性.
主要成果:
- 在72K以下观察到远距离的反铁磁顺序 (Mn1/4Fe1/4Co1/4Ni1/4) PS3.3.
- 所有四种过渡金属元素 (Mn,Fe,Co,Ni) 都参与了一个单一的,统一的磁相过渡.
- 对于不同的元素,确定了不同的旋转方向,这是由于竞争性异构和交换相互作用而产生的.
结论:
- 在高磁体中稳定了一种新型的长距离磁顺序,其旋转方向无序.
- 独特的磁性元素可以协同稳定复杂的磁性状态.
- 这项工作为了解复杂,无序材料中的磁性秩序提供了新的视角.
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