在表轴 (Ga,Mn) 作为微设备中的单个域壁的负内在电阻
H X Tang1, S Masmanidis, R K Kawakami
1Condensed Matter Physics 114-36, California Institute of Technology, Pasadena, California 91125, USA.
Nature
|September 3, 2004
概括
研究人员发现,铁磁半导体中的单个磁域壁 (DW) 始终降低电阻. 在 (Ga,Mn) As 中的这一发现为自旋电子设备提供了洞察力.
科学领域:
- 磁力学和自旋电子学
- 凝聚物质物理学 凝聚物质物理学
- 材料科学是一种材料科学.
背景情况:
- 磁域和磁域壁 (DWs) 在磁力学中至关重要,在自旋电子学中有应用.
- 关于DW电阻的现有研究产生了相互矛盾的结果,使得DW电阻的基本性质没有得到解决.
- 铁磁半导体在自旋电子应用中是金属的有希望的替代品.
研究的目的:
- 为了研究单个磁域壁 (DWs) 的内在电阻.
- 探索铁磁半导体在自旋电子研究中的潜力.
- 解决关于DW电阻的相互矛盾的实验发现.
主要方法:
- 使用由单晶 (Ga,Mn) 构成的微设备作为表层.
- 使用巨大的平面霍尔效应实时观察DW传播.
- 应用磁场来精确定位单个DWs以进行高分辨率磁阻测量.
主要成果:
- 在 (Ga,Mn) As.As.中始终观察到负的内在DW电阻.
- 证明了DW电阻与通道宽度的变化.
- 将观察到的负电阻归因于磁阻中的量子校正.
结论:
- 铁磁半导体中的单个磁域壁表现出负的内在电阻.
- 这一发现为DW行为提供了更清晰的理解,这对于自旋电子设备开发至关重要.
- 结果表明,量子校正显著影响这些材料中的磁阻.
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