Temperature dependence of the conductivity of the electronic crystal

TL;DR

This paper investigates how the conductivity of a 2D electronic crystal varies with temperature, revealing a crossover from thermal activation to variable range hopping at low temperatures.

Contribution

It provides a detailed analysis of the temperature-dependent transport mechanisms in 2D electronic solids, highlighting the transition between different conduction regimes.

Findings

Thermal activation dominates at higher temperatures.

Variable range hopping becomes significant at low temperatures.

A crossover between transport mechanisms is experimentally observable.

Abstract

We study the temperature dependence of the conductivity of the 2D electronic solid. In realistic samples, a domain structure forms in the solid and each domain randomly orients in the absence of the in-plane field. At higher temperature, the electron transport is governed by thermal activation form of $\sigma_{xx}(T)\propto e^{-\Delta_0/k_BT}$. The impurities will localize the electron states along the edges of the crystal domains. At sufficient low temperature, another transport mechanism called Mott's variable range hopping mechanism, similar to that in a disorder insulator takes effect. We show that as the temperature decreases, a crossover from the fixed range hopping of the transport to the variable range hopping of transport in the 2D electron system may be experimentally observed.