Nonlinear nonreciprocal transport in antiferromagnets free from spin-orbit coupling

Abstract

Relativistic spin-orbit coupling is a fundamental source of nonlinear nonreciprocal transport. It has been believed that large spin-orbit coupling is necessary to cause nonlinear nonreciprocal transport, which strongly narrows down candidate materials. Here, the authors theoretically propose an alternative mechanism of nonlinear nonreciprocal transport using local spin scalar chirality instead of spin-orbit coupling. They demonstrate two types of nonlinear nonreciprocal transport and clarify their microscopic parameter conditions. The findings significantly promote emergent noncentrosymmetric physics in the magnetic phase.