在铁磁旋转子CuCr2Se4-xBrx中,无消耗的异常霍尔电流
Wei-Li Lee1, Satoshi Watauchi, V L Miller
1Department of Physics, Princeton University, Princeton, NJ 08544, USA.
概括
铁磁体中的异常霍尔电流是无散射的,独立于散射. 这项研究证实了特定材料CuCr2Se4-xBrx的这种性质,这对目前的Spin-Hall研究有意义.
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
- 固态物理 固态物理
背景情况:
- 在铁磁体中应用的电场会产生一个异常的霍尔电流 (JH),垂直于磁化 (M).
- 无散射性质的JH,独立于散射速率,一直是物理学中的一个长期争论.
- 以前的实验证据仍然没有确定性.
研究的目的:
- 通过实验解决关于异常的霍尔电流 (JH) 是否无散射的争论.
- 为了研究可调节的铁磁材料中电阻和JH之间的关系.
- 探索对目前的旋转厅产生的影响和研究.
主要方法:
- 使用铁磁螺旋CuCr2Se4-xBrx,其中电阻 (rho) 可以通过改变含量 (x) 而不会影响磁化 (M) 来显著变化.
- 在低温 (5 克尔文) 测量了异常的霍尔电流 (JH) 和电场 (E).
- 计算了每个载体的正常化霍尔电流 (JH/E).
主要成果:
- 证明了正常化的霍尔电流 (JH/E) 在CuCr2Se4-xBrx中在广泛的电阻范围内保持不变.
- 展示了增加数量级的电阻力不会改变JH/E比率.
- 证实了异常霍尔电流的无散射性质.
结论:
- 铁磁体中异常的霍尔电流 (JH) 的确没有散射,不受材料的散射速率的影响.
- 这一发现为异常霍尔效应的理论模型提供了重要的实验验证.
- 这些结果对在散装铁磁材料中实际产生和研究旋-霍尔电流具有重大意义.
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