Pressure-controlled anomalous Hall conductivity in the half-Heusler antiferromagnet GdPtBi

Abstract

Controlling the intrinsic anomalous Hall conductivity (AHC) induced by Berry curvature is of significance in potential applications. Half-Heusler antiferromagnet GdPtBi provides an excellent platform to design and control the AHC, owing to its simple band structure near the Fermi level. Here, we systematically study the pressure-dependent magnetotransport properties of GdPtBi, in which the AHC can be continuously tuned by applying hydrostatic pressure. While the band structure and magnetism of GdPtBi bear minor changes below 2 GPa, the AHC decreases progressively with increasing pressure, and eventually vanishes at $P=1.5\phantom{\rule{0.16em}{0ex}}\mathrm{GPa}$. The chiral anomaly effect and electronic structure calculations further manifest that the Weyl nodes persist in this pressure range under magnetic field. Further analysis indicates that the disappearance of AHC in GdPtBi originates from the shift of the Fermi level relative to the Weyl nodes or the change of the canted spin structure of Gd ions in finite magnetic field under pressure. Our results show that pressure is an effective way to tune the anomalous Hall effect in magnetic topological semimetals.