Anisotropic in-plane resistivity in the nematic phase of the iron pnictides

TL;DR

This paper presents a theory explaining anisotropic in-plane resistivity in iron pnictides' nematic phase, linking impurity scattering and spin fluctuations, and predicts doping-dependent sign changes consistent with experimental observations.

Contribution

It introduces a novel theoretical model connecting impurity scattering and spin fluctuations to resistivity anisotropy, explaining experimental signs and doping effects in iron pnictides.

Findings

Explains the sign of resistivity anisotropy in electron-doped systems.

Predicts a sign change of anisotropy with hole doping.

Addresses effects of sample annealing and chemical substitution.

Abstract

We show that the interference between scattering by impurities and by critical spin fluctuations gives rise to anisotropic transport in the Ising-nematic state of the iron pnictides. The effect is closely related to the non-Fermi liquid behavior of the resistivity near an antiferromagnetic quantum critical point. Our theory not only explains the observed sign of the resistivity anisotropy $\Delta\rho$ in electron doped systems, but also predicts a sign change of $\Delta\rho$ upon sufficient hole doping. Furthermore, our model naturally addresses the changes in $\Delta\rho$ upon sample annealing and alkaline-earth substitution.