量子自旋诱导的光效应来自第一原理计算的霍尔边缘状态
Yaqing Yang1,2, Liwen Zhang3, Xiaohong Zheng4
1State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China. zhanglei@sxu.edu.cn.
Physical chemistry chemical physics : PCCP
|June 8, 2023
概括
拓绝缘器纳米带中的缺陷工程通过与旋转相关的光效应 (PGE) 显著增强了自旋光电流. 这一发现突显了它们对先进光旋电子器件的潜力.
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
- 量子物理学 量子物理学 是一种量子物理学.
背景情况:
- 拓绝缘器 (TI) 由于旋转轨道相互作用而具有独特的电子特性.
- 在TI中,量子自旋霍尔边缘状态 (QSHES) 在拓上被保护免受散射.
- 与旋转相关的光效应 (PGE) 提供了一条从光中产生旋转电流的途径.
研究的目的:
- 从理论上研究BiBr和SbBr纳米带中的与旋转相关的光效应 (PGE).
- 了解缺陷在QSHES产生的自旋光电流调节中的作用.
- 探索缺陷工程IT的潜力,用于光旋电子应用.
主要方法:
- 非平衡格林函数 (NEGF) 与密度函数理论 (DFT) 相结合.
- 第一个原则是原子计算.
- 在原始和有缺陷的纳米带中分析由PGE产生的自旋电流.
主要成果:
- 通过QSHES,PGE产生纯自旋电流,独立于光子能量,极化和发生角度.
- 旋转光电流对缺陷非常敏感,尽管QSHES的强度很高.
- 与原始纳米丝带相比,调整缺陷位置显著增加了自旋光电流大小.
结论:
- 缺陷在拓绝缘体纳米带中增强PGE产生的自旋光电流中起着至关重要的作用.
- 缺陷工程为优化光旋电子设备提供了一个有前途的战略.
- 这项研究证明了缺陷工程TI的潜力,用于新的2D光旋电子应用.
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