Mesoscopic conductance fluctuations in graphene

TL;DR

This paper investigates mesoscopic conductance fluctuations in graphene, revealing how elastic and inelastic scattering influence these fluctuations and proposing a method to determine electron temperature.

Contribution

It demonstrates the dependence of conductance fluctuation variance on elastic and inelastic scattering, and shows that correlation energy can measure electron temperature in graphene.

Findings

Strong intervalley scattering suppresses conductance fluctuations.

Variance depends on both elastic and inelastic scattering.

Correlation energy is independent of elastic scattering details.

Abstract

We study fluctuations of the conductance of micron-sized graphene devices as a function of the Fermi energy and magnetic field. The fluctuations are studied in combination with analysis of weak localization which is determined by the same scattering mechanisms. It is shown that the variance of conductance fluctuations depends not only on inelastic scattering that controls dephasing but also on elastic scattering. In particular, contrary to its effect on weak localization, strong intervalley scattering suppresses conductance fluctuations in graphene. The correlation energy, however, is independent of the details of elastic scattering and can be used to determine the electron temperature of graphene structures.