Tunneling anisotropic magnetoresistance in Fe/GaAs/Au junctions: orbital effects

TL;DR

This paper demonstrates that the tunneling anisotropic magnetoresistance (TAMR) effect in Fe/GaAs/Au junctions can be manipulated by magnetic fields, with theoretical insights into the orbital and spin-orbit interactions responsible.

Contribution

It reveals the orbital effects and Dresselhaus spin-orbit coupling as key factors influencing TAMR, highlighting the intrinsic role of bulk inversion asymmetry in the barrier.

Findings

TAMR can be controlled by magnetic field in Fe/GaAs/Au junctions.

Dresselhaus spin-orbit coupling contributes to TAMR with uniaxial symmetry.

Bychkov-Rashba spin-orbit coupling does not significantly affect TAMR.

Abstract

We report experiments on epitaxially grown Fe/GaAs/Au tunnel junctions demonstrating that the tunneling anisotropic magnetoresistance (TAMR) effect can be controlled by a magnetic field. Theoretical modelling shows that the interplay of the orbital effects of a magnetic field and the Dresselhaus spin-orbit coupling in the GaAs barrier leads to an independent contribution to the TAMR effect with uniaxial symmetry, whereas the Bychkov-Rashba spin-orbit coupling does not play a role. The effect is intrinsic to barriers with bulk inversion asymmetry.