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arXiv · 1509.00657

Giant Forward Scattering Asymmetry and Anomalous Tunnel Hall effect at Spin-Orbit-and Exchange-Split Interfaces

T. Huong Dang·H. Jaffrès·T. L. Hoai Nguyen·H. -J. Drouhin
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Abstract

We report on theoretical investigations of scattering asymmetry vs. incidence of carriers through exchange barriers and magnetic tunnel junctions made of semiconductors involving spin-orbit interaction. By an analytical 2?2 spin model, we show that, when Dresselhaus interaction is included in the conduction band of antiparallel magnetized electrodes, the electrons can undergo a large difference of transmission depending on the sign of their incident in-plane wavevector. In particular, the transmission is fully quenched at some points of the Brillouin zone for specific in-plane wavevectors and not for the opposite. Moreover, it is universally scaled by a unique function independent of the spin-orbit strength. This particular feature is reproduced by a 14 ? 14 band k ? p model showing, in addition, corresponding effects in the valence band and highlighting the robustness of the effect, which even persists for a single magnetic electrode. Upon tunneling, electrons undergo an asymmetrical deflection which results in the occurrence of a transverse current, giving rise to a so-called Tunnel Hall Effect.

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T. Huong Dang, H. Jaffrès, T. L. Hoai Nguyen, H. -J. Drouhin. 2015-09-02. Giant Forward Scattering Asymmetry and Anomalous Tunnel Hall effect at Spin-Orbit-and Exchange-Split Interfaces. https://doi.org/10.1103/physrevb.92.060403

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