在一个长轴铁磁磁体中的同位素旋转厅效应
Nozomi Soya1, Michihiro Yamada2,3, Kohei Hamaya2,4
1Department of Applied Physics and Physico-Informatics, Keio University, Yokohama 223-8522, Japan.
Physical review letters
|September 1, 2023
概括
研究人员观察到Fe3Si,一个铁磁体中存在同otropic旋转霍尔效应. 这种效应产生了强大的自旋电流,不受磁化方向的影响,为自旋传输提供了洞察力.
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:
- 旋转霍尔效应 (SHE) 是在材料中产生旋转电流的基本机制.
- 了解铁磁材料中的SHE对于开发自旋电子设备至关重要.
- 之前对铁磁体中SHE的研究经常面临与磁化动力学和脱相相关的挑战.
研究的目的:
- 为了研究在一个经过表轴生长的铁 (Fe3Si) 铁磁体中旋转霍尔效应.
- 为了确定产生的自旋电流是否与磁化相对同otropic.
- 提供关于铁磁系统中自旋电流的产生和传输的基本见解.
主要方法:
- 在Fe3Si薄膜的表面上生长.
- 电磁特性技术用于测量旋转电流的产生.
- 分析旋转霍尔效应对旋转方向和磁化之间的相对方向的依赖.
主要成果:
- 在Fe3Si.中观察了由旋转霍尔效应产生的相当大的自旋电流.
- 发现自旋电流的方向与磁化是非对线的.
- 旋转霍尔电流的大小独立于旋转方向和磁化之间的相对方向,表明一个同otropic SHE.
结论:
- 在Fe3Si中旋转霍尔效应的同otropic性质表明,内在产生的横旋旋组件是免受脱相的保护.
- 这一发现为铁磁体中旋转电流生成和传输的机制提供了基本的见解.
- 结果为使用强大的自旋电流的新型自旋电子设备应用铺平了道路.
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