通过非磁性接触观察两端CISS磁电阻
Md Anik Hossain1, Sara Illescas-Lopez2, Seyedamin Firouzeh1
1Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada.
Nano letters
|June 9, 2025
概括
即使使用非旋转检测电极,也可能发生依赖于度的磁电阻 (MR),这挑战了它总是涉及度诱导的旋转选择性 (CISS) 效应的假设.
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:
- 铁磁 (FM) /非磁 (NM) 系统中的依赖于奇拉性的不对称磁阻 (MR) 通常归因于奇拉性诱导的旋转选择性 (CISS) 效应.
- 该CISS效应假设状介质产生由铁磁电极检测到的自旋偏振电流.
研究的目的:
- 为了研究两端不对称的MR反应的普遍性.
- 为了证明依赖于奇拉度的MR甚至可以通过非旋转检测电极表现出来.
- 为了区分观察到的MR与电磁化性异性 (EMChA).
主要方法:
- 使用非磁性电极与非磁性介质接触.
- 可控地将奇拉性引入通道.
- 测量两端不对称的MR反应.
- 将响应与标准FM/NM电极配置进行比较.
主要成果:
- 即使使用无磁介质和非磁性电极,也观察到依赖于度的不对称MR反应.
- 这种反应表明MR的表现是由于奇拉性,独立于自旋检测电极.
- 当使用标准FM/NM电极时,观察到的效果保持不变,并且与EMChA不同.
结论:
- 在运输实验中观察到依赖于度的MR并不一定意味着度和旋转选择性之间存在直接联系.
- 对于具有非旋转检测电极的系统,CISS效应模型可能需要重新评估.
- 这一发现扩大了对在合和非合物质系统中MR现象的理解.
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