在补偿磁体中的Brillouin区域中心的非相对论旋转分裂
Lin-Ding Yuan1, Alexandru B Georgescu2, James M Rondinelli1
1Department of Materials Science and Engineering, <a href="https://ror.org/000e0be47">Northwestern University</a>, Evanston, Illinois 60208, USA.
Physical review letters
|December 6, 2024
概括
研究人员发现了新的反铁磁体 (AFM) 与非相对论旋转分裂 (NRSS) 超出了变磁体. 这些材料在 Γ 点中打破了旋转退化,使得旋转电流在没有取消的情况下产生.
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
- 固态物理 固态物理
背景情况:
- 替代磁体中的非相对论自旋分裂 (NRSS) 已重新引起对抗铁磁体 (AFM) 的兴趣.
- 现有的变磁体描述并不涵盖所有NRSS AFM.
- 由于AFM缺乏净磁化,因此有可能用于自旋电子应用.
研究的目的:
- 确定NRSS AFM超越变磁体的对称条件.
- 标志着不同的NRSS AFM表现出破碎的旋转退化.
- 用实验材料候选人验证理论模型.
主要方法:
- 对称性分析以确定NRSS的条件.
- 密度函数理论 (DFT) 的计算.
- 研究三元磁性化物 (MnXN_{2}) 和它们的有序变体.
主要成果:
- 确定了一个独特的NRSS AFM类别.
- 在没有旋转轨道合的 Γ 点上证明了断裂的旋转退化.
- 在MnXN_{2} (X=Si,Ge,Sn) 化合物中验证的发现.
结论:
- 扩大了对NRSS合格材料的理解.
- 这些新型AFM可以在没有取消的情况下产生自旋电流.
- 为螺旋电子研究和设备开发提供了新的途径.
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