Finite-temperature conductance of weakly interacting quantum wires with Rashba spin-orbit coupling

TL;DR

This paper calculates how weakly interacting quantum wires with Rashba spin-orbit coupling deviate from perfect conductance at finite temperatures, highlighting the roles of two- and three-particle scattering processes.

Contribution

It provides a novel analysis of finite-temperature conductance deviations in quantum wires with Rashba coupling beyond Luttinger liquid theory.

Findings

Two-particle scattering causes conductance deviations near the Zeeman gap center.

Three-particle scattering dominates for chemical potentials away from the gap center.

Deviations are linked to the nonlinear single-particle spectrum.

Abstract

We calculate the finite-temperature conductance of clean, weakly interacting one-dimensional quantum wires subject to Rashba spin-orbit coupling and a magnetic field. For chemical potentials near the center of the Zeeman gap ($\mu = 0$), two-particle scattering causes the leading deviation from the quantized conductance at finite temperatures. On the other hand, for $|\mu| > 0$, three-particle scattering processes become more relevant. These deviations are a consequence of the strongly nonlinear single-particle spectrum, and are thus not accessible using Luttinger liquid theory. We discuss the observability of these predictions in current experiments on InSb nanowires and in "spiral liquids", where a spontaneous ordering of the nuclear spins at low temperatures produces an effective Rashba coupling.