Electronic transport properties of HiTUS deposited non-colinear antiferromagnet – topological insulator Mn₃Sn-Bi_0.85Sb_0.15 bilayers

Next generation magnetoelectric spin-orbit logic devices require novel materials for spin injection and spin to charge conversion that are compatible with techniques used in industry. Ideally, the spin injection layer will have no ferromagnetic moment and the spin to charge conversion layer will have a larger spin Hall angle than conventional heavy metals. Two materials that meet these criteria are the non-colinear antiferromagnet Mn₃Sn and the topological insulator Bi_0.85Sb_0.15 (BiSb). In this work, we deposit polycrystalline thin film bilayers of Mn₃Sn and Bi­Sb via high target utilization sputtering (HiTUS), which enables independent control of the sputtering plasma energy and density, and study their potential as a spin injector – spin to charge conversion stack. We present results in growth optimization of Mn­₃Sn and Bi­Sb via the HiTUS method, including surface morphology via AFM and crystallinity via XRR and XRD, electronic transport measurements which show the anomalous Hall effect due to the octupole moment of Mn₃Sn and weak antilocalization due to surface state conduction in Bi­Sb_­, and progress in spin injection from the Mn₃Sn layer and spin to charge conversion in the Bi­Sb_­ layer.