Investigation of nonlinear Hall effect induced by Berry Curvature dipole in a topological semimetal

The Hall effects in a quantum system, such as quantum Hall effect (QHE) and quantum anomalous Hall effect (QAHE) have become an essential topic in condensed matter physics. Recently, a new type of Hall effect has been found in topological semimetals possessing a time-reversal symmetry in which the Hall conductivity is proportional to the square of the driving current. This unusual Hall signal is resulting from Berry curvature dipole (BCD) allowed from broken inversion symmetry. In this presentation, we discuss electronic and transport properties of a topological semimetal exhibiting BCD-induced nonlinear Hall effect using angle-resolved photoemission spectroscopy, first-principles calculations, and transport measurements. We find the origin of the substantial BCD hotspots contributed from the partially occupied spin-orbit split bands.