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arXiv · 1507.04034

Klein Tunneling of Spin Polarized Currents in HgTe Quantum Wells

Davidson R. Viana·Thiago M. Melo·Jakson M. Fonseca·Daniel S. Souza·Winder A. Moura-Melo·Afranio R. Pereira
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Abstract

We investigate the behavior of spin polarized currents in two-dimensional topological insulators (TI). Stationary solutions inside a HgTe/CdTe quantum well (QW) were obtained by Bernevig-Hughes-Zhang (BHZ) model modified by a electric and magnetic barrier inside a non-completely insulating bulk. An attenuated quantum spin Hall (QSH) effect occurs in the gaped region with an apparent Klein-like paradox. Even more interesting, for strong potential regime, the interaction between the quasiparticles and the barriers allows spin inversion of this electronic states in a distinct channel conduction. Thus, our findings suggest a mechanism to manipulated spin polarized currents in this system.

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Davidson R. Viana, Thiago M. Melo, Jakson M. Fonseca, Daniel S. Souza, Winder A. Moura-Melo, Afranio R. Pereira. 2015-07-14. Klein Tunneling of Spin Polarized Currents in HgTe Quantum Wells. https://arxiv.org/abs/1507.04034

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