Spin-orbit torque generated by a ferromagnet/a metallic glass bilayer

Large charge-spin conversion in a metallic glass is expected due to disordered atomic structure. Here, we report spin-orbit torque in ferromagnet/metallic glass bilayer, in which spin current generated in the metallic glass injects into the ferromagnetic layer and exerts spin-transfer torque. The effective spin-Hall angle in Pd-Si binary alloy/Ni-Fe bilayer is evaluated by modulation of damping and spectrum shape analysis in spin-torque ferromagnetic resonance experiment. Our results indicate that Pd-Si metallic glass has large charge-spin conversion efficiency compared with Pd.