Theory of Anisotropic Hopping Transport due to Spiral Correlations in the Spin-Glass Phase of Underdoped Cuprates

TL;DR

This paper presents a theoretical model explaining the large in-plane resistivity anisotropy observed in the spin-glass phase of underdoped cuprates, attributing it to spiral spin correlations affecting hole transport.

Contribution

It introduces a novel theoretical framework linking spiral spin states to anisotropic hopping transport in cuprates, aligning well with experimental data.

Findings

Resistivity anisotropy reaches up to 90% in the variable-range hopping regime.

Anisotropy decreases with increasing temperature.

The model explains anisotropy without assuming charge self-organization.

Abstract

We study the in-plane resistivity anisotropy in the spin-glass phase of the high-$T_{c}$ cuprates, on the basis of holes moving in a spiral spin background. This picture follows from analysis of the extended $t-J$ model with Coulomb impurities. In the variable-range hopping regime the resistivity anisotropy is found to have a maximum value of around 90%, and it decreases with temperature, in excellent agreement with experiments in La$_{2-x}$Sr$_x$CuO$_4$. In our approach the transport anisotropy is due to the non-collinearity of the spiral spin state, rather than an intrinsic tendency of the charges to self-organize.