Nonlinear electric transport in odd-parity magnetic multipole systems: Application to Mn-based compounds

TL;DR

This paper theoretically investigates nonlinear electric transport phenomena in odd-parity magnetic multipole systems, revealing unique effects such as giant nonlinear Hall effect and magnetically-induced Berry curvature dipole in Mn-based compounds.

Contribution

It introduces a classification of nonlinear responses in $ ext{PT}$-symmetric magnetic systems and uncovers novel nonlinear conductivity effects specific to odd-parity magnetic multipole materials.

Findings

Identification of nonlinear Hall effect in Mn-based magnets

Proposal of nematicity-assisted dichroism

Demonstration of magnetically-induced Berry curvature dipole

Abstract

Violation of parity symmetry gives rise to various physical phenomena such as nonlinear transport and cross-correlated responses. In particular, the nonlinear conductivity has been attracting a lot of attentions in spin-orbit coupled semiconductors, superconductors, topological materials, and so on. In this paper we present theoretical study of the nonlinear conductivity in odd-parity magnetic multipole ordered systems whose $\mathcal{PT}$-symmetry is essentially distinct from the previously studied acentric systems. Combining microscopic formulation and symmetry analysis, we classify the nonlinear responses in the $\mathcal{PT}$-symmetric systems as well as $\mathcal{T}$-symmetric (non-magnetic) systems, and uncover nonlinear conductivity unique to the odd-parity magnetic multipole systems. A giant nonlinear Hall effect, nematicity-assisted dichroism and magnetically-induced Berry curvature dipole effect are proposed and demonstrated in a model for Mn-based magnets.