在kagome Weyl半金属中的反铁磁旋转扭矩二极管效应
Shoya Sakamoto1, Takuya Nomoto2,3,4, Tomoya Higo5,6,7
1The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Japan. shoya.sakamoto@issp.u-tokyo.ac.jp.
Nature nanotechnology
|December 3, 2024
概括
研究人员展示了一种使用旋转轨道扭矩控制反铁磁旋转的新方法,使微波设备更快. 这种反铁磁旋转扭矩二极管效应为下一代电信提供了一个有希望的途径.
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:
- 基于铁磁铁的自旋电子技术已经有了先进的微波设备.
- 反铁磁铁具有更快操作的潜力,但很难操纵.
- 用微波电流控制反铁磁秩序一直是一个重大挑战.
研究的目的:
- 探索使用直流旋转轨道扭矩来控制反铁磁秩序.
- 研究反铁磁铁中连贯自旋旋转和微波电流之间的合.
- 为高速微波应用开发一种新的整形效应.
主要方法:
- 通过使用直流旋转轨道扭矩,在W/Mn3Sn表轴双层中诱导反铁磁旋转的连贯旋转.
- 演示了旋转旋转和微波电流之间的高效合.
- 测量通过纠正产生的DC异常霍尔电压.
- 执行数值模拟以了解底层的纠正机制.
主要成果:
- 成功诱导了反铁磁旋转的连贯旋转.
- 实现了自旋旋转与微波电流的高效合.
- 通过校正观察到一个DC异常的霍尔电压,称为反铁磁自旋扭矩二极管效应.
- 由于交换互动稳定,输出电压表现出最小的频率依赖 (从10-30 GHz下降10%).
- 纠正信号被归因于微波旋转轨道扭矩的奇拉旋转旋转的频率调制.
结论:
- 反铁磁旋转扭矩二极管效应为微波信号纠正提供了一个新的机制.
- 最小的频率依赖使得这种效果适用于高速微波设备.
- 这项研究为开发基于反铁磁自旋电子的下一代电信技术铺平了道路.
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