Spin orbit torque switching of magnetization in the presence of two different orthogonal spin-orbit magnetic fields

Abstract

Switching of magnetization by spin-orbit torque in the (Ga,Mn)(As,P) film was studied with currents along 100 crystal directions and an in-plane magnetic field bias. This geometry allowed us to identify the presence of two independent spin-orbit-induced magnetic fields: the Rashba field and the Dresselhaus field. Specifically, we observe that when the in-plane bias field is along the current (I || Hbias), switching is dominated by the Rashba field, while the Dresselhaus field dominates magnetization reversal when the bias field is perpendicular to the current (I ⊥ Hbias). In our experiments, the magnitudes of the Rashba and Dresselhaus fields were determined to be 2.0 and 7.5 Oe, respectively, at a current density of 8.0 × 105 A/cm2.