Chiral anomaly-induced nonlinear Hall effect in spin-orbit coupled noncentrosymmetric metals

TL;DR

This paper investigates the nonlinear Hall effect induced by chiral anomaly in spin-orbit coupled noncentrosymmetric metals, revealing its dependence on magnetic field, impurity scattering, and band tilt, with implications for experimental design.

Contribution

It demonstrates the chiral-anomaly-induced nonlinear Hall response in SOC-NCMs, including its anisotropic behavior and dependence on impurity scattering and band tilt.

Findings

Nonlinear Hall response exhibits quadratic magnetic field dependence.

Magnetic impurities modify the magnitude but not the qualitative behavior.

Band tilt induces anisotropic response and sign reversal.

Abstract

Recent studies have shown that chiral anomaly is not limited to Weyl semimetals (WSMs), but are also shown by a larger class of materials called spin orbit coupled noncentrosymmetric metals (SOC-NCMs),which has shed more insight into the origin of chiral anomaly as a Fermi surface property rather than a nodal property. In this study, we explore nonlinear transport responses in SOC-NCMswithin the framework of semiclassical dynamics, employing the Maxwell-Boltzmann transport theory augmented by charge conservation and momentum-dependent scattering processes. We take into account both non-magnetic and magnetic impurity scattering mechanisms. We demonstrate that the chiral-anomaly-induced nonlinear Hall (CNLH) response exhibits a characteristic quadratic dependence on the applied magnetic field and remains negative for both types of impurities. We find that magnetic scatterers leading to enhanced/suppressed interband scattering modifies the magnitude of the signal, but does not affect its qualitative behavior. In contrast, the presence of tilt in the band dispersion induces a pronounced anisotropic response, including a magnetic-field-direction dependent sign reversal that can be categorized into weak and strong regimes. Furthermore, the CNLH response shows substantial directional anisotropy governed by the relative orientation of the external magnetic field and the tilt vector. Our findings will be helpful in designing the experimental setup to get direction-dependent conductivity, which can be tuned externally with the help of magnetic impurity sites.