Spin Hall magnetoresistance and spin orbit torque efficiency in Pt/FeCoB bilayers

The spin Hall magnetoresistance (SMR) of Pt/FeCoB bilayers with in-plane magnetocrystalline anisotropy was analysed with respect to a second order effect in the sensing current which acts, through the spin Hall effect in Pt, as a torque on the magnetization of the ferromagnetic layer and changes slightly its configuration. This leads to a small current dependent shift of the SMR curves in field that allows, in structures with a multidomain state (e.g. Hall bars), the determination of the sign of the magnetic remanence. The SMR measurements were performed as a function of the Pt thickness and the spin Hall angle, the diffusion length and the field-like and damping like SOT efficiency were determined. The results were compared with the values obtained from harmonic Hall voltage and SOT-ferromagnetic resonance (FMR) measurements and show a good agreement.