Platinum composition dependence of spin-orbit torque in (Fe0.8Mn0.2)1− x Pt x single-layer ferromagnet

We have investigated the effect of the Pt composition on the spin–orbit torque in a (Fe0.8Mn0.2)1−xPtx single-layer ferromagnet. We observed that while the field-like torque decreases and even reverses sign with increasing the Pt composition, the damping-like torque increases monotonically and reaches 0.99 Oe/(1010 A/m2) in a single-layer (Fe0.8Mn0.2)0.52Pt0.48 film. The results corroborate the anomalous Hall effect and surface spin rotation model presented previously, and the relative ratio between the damping-like and field-like torques can be qualitatively understood as the relative phase change in spin-conserving and spin-flip scattering.