来自特拉赫兹以下生成的反铁磁磁体的旋转电流
Junxue Li1, C Blake Wilson2,3, Ran Cheng1,4
1Department of Physics and Astronomy, University of California, Riverside, CA, USA.
Nature
|January 29, 2020
概括
研究人员在反铁磁异构结构中演示了亚特拉赫兹旋转. 这项工作展示了来自反铁磁共振的纯自旋电流的产生和电探测,为超快的自旋电子设备铺平了道路.
科学领域:
- 凝聚物质物理学
- 机器人
- 材料科学
背景情况:
- 反铁磁铁提供比超快设备的铁磁铁更快的旋转动力.
- 在抗铁磁体中产生和电气检测自旋电流仍然是一个挑战.
研究的目的:
- 在反铁磁异构结构中演示子特拉赫兹自旋和纯自旋电流的电探测.
- 在高频率的反铁磁体中研究磁激发和自旋电荷转换.
主要方法:
- 使用单轴反铁磁Cr2O3和重金属 (Pt,β-Ta) 制造异构结构.
- 在0.240 THz和2.7 T的反铁磁共振 (AFMR) 的激发,以及在10.5 T的第二个共振.
- 通过反旋霍尔效应对产生的自旋电流进行电探测.
主要成果:
- 在Cr2O3/重金属异构中成功生成和检测来自AFMR和第二次共振的纯自旋电流.
- 在切换金属探测器 (Pt/Ta) 或磁场方向时,通过电压极性逆转来确认纯自旋电流.
- 温度依赖性和自旋西贝克效应测量显示了对自旋电流的连贯和不连贯的马格农贡献.
结论:
- 这项研究明确地证明了反铁磁体中低于特拉赫兹的自旋和纯自旋电流的电探测.
- 这些发现突出了独特的磁激发特征和它们在高频率的自旋电荷转换中的作用.
- 这些结果为开发基于反铁磁材料的超高速旋转器件开辟了新的途径.
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