Bias-dependent tunneling anisotropic magnetoresistance in antiferromagnetic Pd-doped FeRh-based junctions

Abstract

We report the bias-dependent tunneling anisotropic magnetoresistance (TAMR) in antiferromagnetic α′-Fe(Rh0.98Pd0.02)/MgO/γ-Fe(Rh0.98Pd0.02) junctions. The TAMR effect is driven by the antiferromagnetic-ferromagnetic phase transition of α′-Fe(Rh0.98Pd0.02) and concomitantly large variation of the density of states (DOS) near the Fermi level. It exhibits polarity reversion behavior with increasing bias voltage, i.e., negative and positive polarities for low and high bias voltages, respectively. Such bias-dependent TAMR is comprehended by first-principle calculations, where a crossing point and subsequent magnitude-reversion emerge between the DOS of antiferromagnetic and ferromagnetic phases of α′-Fe(Rh0.98Pd0.02). Harnessing the tunneling behavior by a feasible bias voltage in an antiferromagnet-based junction is a frontier of great promise in antiferromagnet spintronics.