由反铁磁交换驱动的奇偶平价磁力
Yue Yu1, Magnus B Lyngby2, Tatsuya Shishidou1
1University of Wisconsin-Milwaukee, Department of Physics, Milwaukee, Wisconsin 53201, USA.
Physical review letters
|August 12, 2025
概括
我们提出了一个新的框架,用于在没有旋转轨道合 (SOC) 的反铁磁 (AFM) 材料中实现旋转分裂. 这种方法可以通过在AFM状态中诱导奇偶平价旋转分裂来实现新型旋转电子应用.
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
- 这就是Spintronics.
背景情况:
- 实现奇偶平价,时间逆转保存,非相对论旋转分裂对于推进旋转电子学至关重要.
- 传统方法通常依赖于旋转轨道合 (SOC),限制了材料选择和应用.
研究的目的:
- 提出基于群理论的微观框架,用于在没有SOC的反铁磁 (AFM) 状态中诱导奇偶平价自旋分裂.
- 在这些AFM系统中探索竞争的地面状态及其相关命令.
主要方法:
- 在非对称空间组中开发了421个周期翻倍的AFM系统的现象学模型.
- 为这些系统中的119个构建了最小的微观模型.
- 利用密度函数理论 (DFT) 的计算和分析材料数据库 (Magndata).
主要成果:
- 确定了三种竞争的基本状态:奇偶平价旋转分裂,内马特秩序和标量奇偶平价秩序.
- 证明奇偶平价旋转分裂能量尺度是一般的大.
- 显示了标量奇偶平价顺序会产生一个非零的贝里曲率双极,没有SOC.
- 确定了67种候选材料,并证实了Fe基材料中的h波旋转分裂.
结论:
- 拟议的框架提供了一条可行的途径,在没有SOC的情况下在AFM材料中进行非相对论旋转分裂.
- 已识别的基态及其相关顺序为自旋电子和多铁应用开辟了新的途径.
- 这些发现为探索各种材料中的新型电子和磁现象提供了理论基础.
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