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反常位移(Goos—Hanchen位移,即GH位移),实现了弹道电子的自旋分离,为自旋分离器件的设计提供了理论依据。研究结果表明: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;位移在一定条件下可以为正也可以为负;体系中弹道电子的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。基于这些现象,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,这些现象在设计自旋电子学器件上有所作用。
Taking the spin-orbit coupling (SOC) into account, the lateral displacements (Goos-Hanchen 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, a kind of spatial spin beam splitting of ballistic electrons by the displacements is proposed. The results are beneficial in designing some spintronics devices.