2020/09/14 by Joynarayan Mukherjee, T. S. Suraj, Himalaya Basumatary +2 · 1 citation
Physics and Astronomy · #cond-mat.mtrl-sci #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevmaterials.5.014201
published as Phys. Rev. Materials 5, 014201 (2021) · 6 pages, 5 figures
arxiv created 2020/09/14 · arxiv updated 2021/01/13
The two dimensional kagome spin lattice structure of Mn atoms in the family of Mn3X non-collinear antiferromagnets are providing substantial excitement in the exploration of Berry curvature physics and the associated non-trivial magnetotransport responses. Much of these studies are performed in the hexagonal systems, mainly Mn3Sn and Mn3Ge, with the kagome planes having their normal along the [001] direction. In this manuscript, we report our study in the cubic Mn3Pt thin films with their kagome planes normal to the [111] crystal axis. Our studies reveal a hole conduction dominant Hall response with a non-monotonic temperature dependence of anomalous Hall conductivity (AHC), increasing from 9 Ω-1cm-1 at room temperature to 29 Ω-1cm-1 at 100 K, followed by a drop and unexpected sign-reversal at lower temperatures. Similar sign reversal is also observed in magnetoresistance measurements. We attribute this sign reversal to the transition from a Berry curvature dominated AHC at high temperature to a weak canted ferromagnetic AHC response at lower temperature, below 70 K, caused by the reorientation of Mn moments out of the kagome plane. Our above results in thin films of Mn3Pt make advances in their integration with room temperature antiferromagnetic spintronics.