中心对称半导体中的圆形光电流具有隐藏的自旋极化
Kexin Wang1, Butian Zhang2, Chengyu Yan1
1MOE Key Laboratory of Fundamental Physical Quantities Measurement and Hubei Key Laboratory of Gravitation and Quantum Physics, PGMF and School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, China.
Nature communications
|October 19, 2024
概括
隐藏自旋偏振的中心对称材料可以产生自旋偏振的圆形光电流. 这一突破使得通过使用量身定制的光线打破全球反向对称性,使得自旋电子设备的应用成为可能.
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:
- 具有位点反向不对称的中心对称材料表现出隐藏的旋转极化,由于保留了全局反向对称性,很难转化为旋转电流.
- 现有的旋转电流生成方法通常需要打破全局逆向对称或应用电偏差.
研究的目的:
- 为了在没有电偏差的中心对称过渡金属二二半导体中演示旋极化的圆形光电流.
- 探索使用空间变化的循环极化光产生自旋梯度和循环电流的机制.
- 为了利用圆形光电流来探测旋转极化和反旋转霍尔效应.
主要方法:
- 利用空间变化的循环极化光来打破中心对称材料中的全球反向对称性.
- 研究圆形光电流对电极配置,照明位置和光束点大小的依赖.
- 在不同的激发波长和温度下使用圆形光流来探测旋转偏振和逆旋转霍尔效应.
主要成果:
- 在正常发生率下,成功地在中心对称过渡金属二二二氧化物半导体中产生了自旋极化圆形光电流.
- 证明空间不均的光会打破全球反转对称性,通过反转霍尔效应诱导旋转梯度和循环电流.
- 建立了一种方法来探测隐藏的旋转偏振和反旋转霍尔效应,使用圆形光电流.
结论:
- 具有隐藏的自旋偏振和不消失的果曲率的中心对称材料对于自旋电子设备应用是可行的.
- 空间变化的循环极化光提供了一种新的途径,可以在中心对称材料中产生和控制自旋电流.
- 展示的光电流生成和探测技术为先进的自旋电子功能开辟了新的途径.
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