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

Abstract

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

CLC Number:

O436.1

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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