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

TL;DR

This paper presents a theoretical study revealing giant asymmetries in electron transmission and a novel Tunnel Hall Effect at spin-orbit and exchange-split semiconductor interfaces, with potential implications for spintronic devices.

Contribution

It introduces a new analytical and numerical framework demonstrating large transmission asymmetries and a Tunnel Hall Effect due to Dresselhaus spin-orbit interaction in magnetic tunnel junctions.

Findings

Transmission asymmetry depends on in-plane wavevector sign.

Effect persists even with a single magnetic electrode.

Universal scaling function independent of spin-orbit strength.

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.