通过晶体对称性对CrSb的变磁顺序进行操纵
Zhiyuan Zhou1, Xingkai Cheng2, Mengli Hu2
1Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering, Tsinghua University, Beijing, China.
Nature
|February 12, 2025
概括
研究人员通过改变晶体对称性来操纵抗氧化物薄膜的磁变秩序. 这项工作解锁了室温异常的霍尔效应, 并为磁性记忆技术提供了新的途径.
科学领域:
- 凝聚物质物理
- 材料科学
- 磁力学
背景情况:
- 变磁是一种由晶体对称和尼尔向量定义的独特的磁性秩序.
- 现有的研究集中在调整Neel向量的方向,而不是晶体对称性,用于改变磁性.
- 操纵晶体对称性提供了一个有希望的,但具有挑战性的, 控制变磁秩序的途径.
研究的目的:
- 通过控制抗氧化物 (CrSb) 薄膜中的晶体对称性来证明变磁秩序的操纵.
- 为了研究Dzyaloshinskii-Moriya矢量和磁空间对称性在重建反磁秩序中的作用.
- 通过晶体对称重建来探索室温自发异常霍尔效应的产生.
主要方法:
- 使用抗氧化物 (CrSb) 薄膜进行实验研究.
- 研究了Dzyaloshoshinskii-Moriya矢量和磁空间对称性的相互作用.
- 分析了基于电流诱导的旋转极化和Dzyaloshoshinskii-Moriya向量的变磁顺序的切换模式.
主要成果:
- 通过在CRSB膜中重建晶体对称性, 成功操纵了磁变秩序.
- 观察到一个室温自发异常的霍尔效应.
- 确定了由Dzyaloshinskii-Moriya向量和电流诱导的旋转极化控制的不同的切换模式 (场辅助和无场).
- 证明了Dzyaloshinskii-Moriya向量的作用在创造不对称的能量障碍和驱动力.
结论:
- 重建晶体对称性提供了一种用于改变磁性秩序的新方法.
- 这些发现对磁性记忆和纳米振荡器技术有影响.
- 这项工作为跨学科的研究开辟了道路,
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