在一个挫败的磁铁中旋转扭矩 skyrmion 共振
Nirel Bernstein1, Hang Li2,3, Benjamin Assouline1
1Institute of Applied Physics, The Hebrew University of Jerusalem, Jerusalem, Israel.
Nature communications
|May 18, 2025
概括
研究人员在丧的Fe3Sn2磁铁中探索了电流驱动的 skyrmion共振. 他们观察到独特的模式激发和线宽调制,揭示了对旋转扭矩和潜在传感器应用的洞察力.
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:
- 像Fe3Sn2这样的丧磁体对旋转电子具有吸引力的特性,包括稳定的 skyrmions 和大型拓式霍尔效应.
- 这些材料中电流诱导的螺旋转换与自我诱导的旋转扭矩现象有关.
- 了解 skyrmion 动态及其对外部刺激的反应对于设备应用至关重要.
研究的目的:
- 为了研究Fe3Sn2磁铁中的电流驱动的 skyrmion共振技术.
- 分析由自我诱导的旋转扭矩激发的特定 skyrmion 模式.
- 探索直流对斯基米子共振线宽的影响及其与旋转轨道扭矩的关系.
主要方法:
- 利用时间解析的光学测量技术来探测斯基米翁动力学.
- 采用微磁模拟来理解线宽扩展机制.
- 进行了互补的平面大厅测量,以分析电子运输贡献.
主要成果:
- 鉴定了只有呼吸和反时钟方向旋转的斯基米安模式的激发,与主导Dzyaloshinskii-Moriya相互作用的系统不同.
- 在应用直流电流时观察到 skyrmion 共振线宽的调制.
- 确定了有效的自旋霍尔导电性,并确定了实空间和k空间自旋纹理的贡献.
结论:
- 这项研究为挫败的磁系统中自旋扭矩的异构性提供了新的见解.
- 这些发现凸显了 skyrmion 共振作为对自旋电流的敏感传感器的潜力.
- 独特的模式选择性为控制磁纹的操纵提供了一条途径.
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