内在的非线性旋转霍尔效应和对垂直磁化的操纵
Hui Wang1, Huiying Liu2, Xukun Feng3
1Nanyang Technological University, Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Singapore 637371, Singapore.
Physical review letters
|February 21, 2025
概括
我们在非磁性材料中发现了一种新的非线性旋转霍尔效应,使先进的记忆技术能够高效地产生旋转电流. 这一突破为无磁场磁切换提供了一条道路,这对于下一代数据存储至关重要.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 这就是Spintronics.
- 材料科学是一种材料科学.
背景情况:
- 旋转霍尔效应 (SHE) 是旋转电子学中的一个关键现象,它将电荷电流转换为旋转电流.
- 目前用于产生自旋电流的方法通常依赖于外部磁场或特定材料特性.
- 下一代信息存储需要高效,无磁场的磁化切换.
研究的目的:
- 提出并从理论上描述一种新的内在非线性旋转霍尔效应 (NL-SHE).
- 探索NL-SHE在垂直磁化无场切换方面的潜力.
- 为了确定在室温下呈现显著NL-SHE的材料系统.
主要方法:
- 对内在非线性自旋霍尔效应的微观理论的开发.
- 对带几何量和拓节点特征的分析,这些特征有助于NL-SHE.
- 第一个原则是计算预测和验证特定材料中的效应.
主要成果:
- 通过NL-SHE在非磁性材料中展示对线性自旋电流的产生,在这种材料中,线性响应是禁止的.
- 确定波段几何和拓节点特征作为NL-SHE的关键支持者.
- 在拓金属PbTaSe_{2}和PdGa.的室温下预测明显的NL-SHE.
结论:
- 本质的非线性旋转霍尔效应代表了旋转运输中的根本性新反应.
- NL-SHE提供了一个有前途的途径,用于自旋电子设备的无磁场磁化切换.
- 这一发现为利用非线性自旋现象的新型自旋电子应用开辟了道路.
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