DC resistivity at the onset of spin density wave order in two-dimensional metals

TL;DR

This paper investigates how spin density wave quantum criticality in two-dimensional metals affects DC resistivity, highlighting the role of disorder and hot spot scattering in producing linear-in-temperature resistivity.

Contribution

It introduces a framework for calculating DC transport near quantum critical points, emphasizing the impact of disorder and hot spot scattering on resistivity behavior.

Findings

Resistivity is linear in temperature at low T due to disorder effects.

Hot spot scattering contributes to residual resistivity and T-linear corrections.

Quantum critical fluctuations influence transport properties across the Fermi surface.

Abstract

The theory for the onset of spin density wave order in a metal in two dimensions flows to strong coupling, with strong interactions not only at the `hot spots', but on the entire Fermi surface. We advocate the computation of DC transport in a regime where there is rapid relaxation to local equilibrium around the Fermi surface by processes which conserve total momentum. The DC resistivity is then controlled by weaker perturbations which do not conserve momentum. We consider variations in the local position of the quantum critical point, induced by long-wavelength disorder, and find a contribution to the resistivity which is linear in temperature (up to logarithmic corrections) at low temperature. Scattering of fermions between hot spots, by short-wavelength disorder, leads to a residual resistivity and a correction which is linear in temperature.