B-linear magnetoresistance from correlated disorder

Magnetoresistance, the change in resistivity as a function of an applied magnetic field B, grows quadratically with the magnetic field in conventional metals. Recent experiments on several correlated electronic platforms, such as cuprates, pnictides and moire graphene observe linear in B magnetoresistance, contrary to usual expectations. We will argue that B-linear magnetoresistance arises ubiquitously in proximity to certain symmetry-broken ordered phases - when the order parameter has a large finite momentum Q (e.g., a charge density wave), or has nodes (e.g., nematic order). Via both analytical arguments and numerical solutions to the Boltzmann equation, we will demonstrate the presence of linear magnetoresistance in both cases, albeit due to completely different physical reasons. In addition, we will discuss upper and lower bounds to the magnetic fields at which B-linear magnetoresistance is observed, and comment on the effect of uncorrelated potential disorder. We will conclude with a perspective on the applicability of our results to certain material candidates.