Linear magnetoresistance induced by intra-scattering semiclassics of Bloch electrons

TL;DR

This paper reveals that intra-scattering effects, influenced by Berry curvature, magnetic moment, and shift vector, significantly impact weak field magnetoresistance, challenging the traditional focus on inter-scattering effects.

Contribution

It demonstrates that intra-scattering semiclassical effects are as important as inter-scattering effects in magnetoresistance, highlighting overlooked factors like magnetic moment and shift vector.

Findings

Intra-scattering effects can reverse the sign of linear magnetoresistance.

Berry curvature alone induces negative linear magnetoresistance.

Magnetic moment and shift vector alter the magnetoresistance sign.

Abstract

The weak field magnetoresistance has seen a revived interest due to the distinct role played by the momentum-space Berry curvature of Bloch electrons. While most previous studies in this regard focus on the inter-scattering motion of semiclassical Bloch electrons in electromagnetic fields, the intra-scattering effects of the semiclassical dynamics augmented by the Berry curvature, magnetic moment and shift vector on the magnetoresistance have been largely overlooked. Here we uncover that these intra-scattering effects, which are neglected in the field-independent relaxation time approximation to the Boltzmann collision integral, can be as important as the inter-scattering ones. Concrete calculations on the two dimensional gapped Dirac model show that the sign of the negative linear magnetoresistance given by the Berry curvature alone is reversed when one considers the magnetic moment and shift vector.