Robust negative longitudinal magnetoresistance and spin-orbit torque in sputtered PtSn and PtSnFe topological semimetal.

Contrary to topological insulators, topological semimetals possess a nontrivial chiral anomaly that leads to negative magnetoresistance and are hosts to both conductive bulk states and topological surface states with intriguing transport properties for spintronics. Here, we fabricate highly-ordered metallic PtSn and PtSnFe thin films via sputtering technology. Systematic angular dependence (both in-plane and out-of-plane) study of magnetoresistance presents surprisingly robust quadratic and linear negative longitudinal magnetoresistance features for PtSn and PtSnFe, respectively.