含Rashba自旋轨道耦合二维电子气结构中电子反常位移及自旋分离

J4 ›› 2011, Vol. 28 ›› Issue (3): 318-323.

含Rashba自旋轨道耦合二维电子气结构中电子反常位移及自旋分离

杨晓芳

上海大学理学院物理系, 上海 200444

收稿日期:2010-04-08 修回日期:2010-07-12 出版日期:2011-05-28 发布日期:2011-05-20
通讯作者: 李春芳（1964-），上海人，教授，博士生导师，主要从事有限光束和量子物理的研究和教学。 E-mail:cfli@shu.edu.cn
作者简介:杨晓芳，江西吉安人，研究生，主要从事介观体系弹道电子的输运行为研究。 E-mail: yangxf@shu.edu.cn
基金资助:
国家自然科学基金（60806041、60877055），上海市重点学科建设项目（S30105）

Lateral displacement and spin separation in two-dimensional electron gas system with Rashba spin-orbit coupling

YANG Xiao-Fang

Department of Physics, Shanghai University, Shanghai 200444, China

Received:2010-04-08 Revised:2010-07-12 Published:2011-05-28 Online:2011-05-20

摘要/Abstract

摘要：

研究了含Rashba自旋轨道耦合的磁电调制半导体二维电子气中弹道电子的反常位移（Goos-H?nchen位移，即GH位移）。计算中发现，通过调节结构的各个参数包括入射角、磁场强度和Rashba自旋轨道耦合系数，可以有效地调控GH位移，并且在一定条件下可以为负。电子的GH位移和自旋极化态有密切关系，这个自旋相关的位移可以用来分离不同自旋极化的电子束。基于这种现象，提出了一种利用GH位移在半导体2DEG中分离不同自旋极化电子的方法。

关键词: 光电子学, 自旋分离, Goos-Hänchen位移, Rashba自旋轨道耦合

Abstract:

Taking the spin-orbit coupling (SOC) into account, the lateral displacements（Goos-Hänchen shift，or GH shift）of ballistic electrons in a two-dimensional electron gas system modulated by ferromagnetic stripe and external voltage is investigated. Spin separation is realized by the GH shift, which provide theoretical foundation for designing spin separation devices. The conclusions are as follows. These anomalous lateral displacements can be tuned effectively by adjusting the incidence angles, magnetic strength of ferromagnetic stripe and Rashba SOC coefficient. It is shown that the lateral displacements can be negative as well as positive. The displacements are related to the spin polarization, which can be used to separate the different spin-polarization electrons. Based on these phenomena, it is proposed a kind of spatial spin beam splitting of ballistic electrons by the displacements. These phenomena have some potential applications in designing some spintronics devices.

Key words: optoelectronics, spin separation, Goos-Hänchen shift, Rashba spin-orbit coupling

中图分类号:

O436.1

杨晓芳. 含Rashba自旋轨道耦合二维电子气结构中电子反常位移及自旋分离[J]. J4, 2011, 28(3): 318-323.

YANG Xiao-Fang. Lateral displacement and spin separation in two-dimensional electron gas system with Rashba spin-orbit coupling[J]. J4, 2011, 28(3): 318-323.

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