Giant interfacial spin-orbit scattering contribution to spin transport in Mn3Sn/Pt bilayers

We have probed the contribution of interfacial spin-orbit scattering to spin transport in Mn3Sn/Pt bilayers in the temperature range from 5 K to 300 K. Generally, the spin transport of Mn3Sn/Pt bilayers depends on both magnetic order and giant interfacial spin-orbit scattering. The magnetic order transition characteristics of Mn3Sn have been first confirmed by the anomalous Hall effect measurement, and the presence of giant interfacial spin-orbit scattering has dramatically modified the extrinsic scattering mechanisms. Robust and quantitative descriptions for the interfacial spin-orbit scattering contribution have been given. Key parameters for spin transport have been extracted through spin Hall magnetoresistance and weak localization measurements to uncover further the contributions of giant interfacial spin-orbit scattering. These results illustrate the unique role the interfacial properties play in defining spin transport in noncollinear antiferromagnet/heavy metal bilayer systems, which has opened novel strategies to design spintronic devices.