Thermal and thermoelectric properties of an antiferromagnetic topological insulator MnBi2Te4

Abstract

The discovery of an intrinsic antiferromagnetic topological insulator (AFMTI) in ${\mathrm{MnBi}}_{2}{\mathrm{Te}}_{4}$ has attracted intense attention, most of which lies in its electrical properties. In this paper, we report electronic, thermal, and thermoelectric transport studies of this newly found AFMTI. The temperature and magnetic field dependence of its resistivity, thermal conductivity, and Seebeck coefficient indicate strong coupling between charge, lattice, and spin degrees of freedom in this system. Furthermore, ${\mathrm{MnBi}}_{2}{\mathrm{Te}}_{4}$ exhibits a large anomalous Nernst signal, which is associated with nonzero Berry curvature of the field-induced canted antiferromagnetic state.