Magnetotransport properties and giant anomalous Hall angle in the half-Heusler compound TbPtBi

Abstract

Magnetic lanthanide half-Heuslers (RPtBi; R being the lanthanide) represent an attractive subgroup of the Heusler family and have been identified as ideal candidates for time-reversal symmetry-breaking topological Weyl semimetals. In this paper, we present the detailed analysis of the magnetotransport properties of frustrated antiferromagnet TbPtBi. This material shows large, nonsaturating magnetoresistance (MR) with unusual magnetic field dependence. The MR of TbPtBi is significantly anisotropic with respect to the magnetic field, applied along different crystallographic directions, and indicates the anisotropic nature of the Fermi surface. The chiral-anomaly-induced negative longitudinal magnetoresistance confirms the presence of Weyl fermions. At low temperature, Berry-phase-driven large anomalous Hall conductivity has been observed. The calculated anomalous Hall angle is the largest reported so far.