Polarized neutron reflectometry characterization of perpendicular magnetized Ho3Fe5O12 films with efficient spin-orbit torque induced switching

Rare-earth iron garnet films with perpendicular magnetic anisotropy (PMA) are important to develop magnon-based spintronic devices. In this study, high quality epitaxial Ho3Fe5O12 (HoIG) films with PMA are fabricated on (111) Y3(Sc2Ga3)O12 substrates by sputtering. The magnetization compensation temperature of HoIG films is determined to be 130 K, highly consistent with its bulk value. The magnetic dead layer at the interface is quantified as thin as about 0.6 nm through polarized neutron reflectivity. Furthermore, spin–orbit torque switching in HoIG/Pt films is realized with the threshold current density of 1.4 × 1011 A/m2 and assisting field as small as 10 Oe. These results provide one more alternative for spintronic materials using compensated ferrimagnetic insulators.