Temperature dependence of the normal-state Hall coefficient of a quasi-one-dimensional metal

TL;DR

This paper presents a comprehensive theory of the temperature-dependent Hall effect in quasi-one-dimensional conductors, accounting for variable electron relaxation times and predicting temperature-induced sign changes in the Hall coefficient.

Contribution

It introduces a systematic model that describes the Hall effect in Q1D conductors considering relaxation time variations and magnetic field strength effects, including sign reversals.

Findings

Hall coefficient saturates at high temperatures at a specific value.

Temperature dependence and sign change of the Hall coefficient at low temperatures.

Sign changes occur in weak magnetic fields but not in strong fields.

Abstract

We develop a systematic theory of the Hall effect in Q1D conductors in both weak and strong magnetic fields for a model where the electron relaxation time varies over the Fermi surface. At high temperatures, the Hall coefficient saturates at the value $-\beta/ecn$, where the dimensionless coefficient $\beta$ is determined by the curvature of the longitudinal dispersion law of electrons, $e$ the electron charge, $c$ is the speed of light, and $n$ is the hole concentration. At low temperatures, where a strong variation of the relaxation rate over the Fermi surface develops in the form of ``hot spots'', the Hall coefficient becomes temperature-dependent and may change sign for a particular choice of the transverse dispersion law parameters. In our model, the sign changes in a weak, but not in a strong magnetic field.