Universal scaling of resistivity in bilayer graphene

TL;DR

This paper investigates the temperature-dependent electrical resistivity of bilayer graphene, revealing a universal scaling behavior linked to electron-hole puddle fluctuations, and provides theoretical insights into charge inhomogeneity effects.

Contribution

It demonstrates that resistivity in bilayer graphene follows a universal scaling law related to charge puddle fluctuations, supported by empirical and theoretical analysis.

Findings

Resistivity increases as temperature decreases due to charge puddles.

Electrical resistivity follows a universal scaling curve.

The scaling parameter quantifies electron-hole puddle fluctuations.

Abstract

We report the temperature dependent electrical transport properties of gated bilayer graphene devices. We see a clear evidence of insulating behavior due to electron-hole charge puddles. The electrical resistivity increases while the mobility decreases with decreasing temperature, a characteristic due to carrier inhomogeneity in graphene. The theoretical fittings using an empirical formula of single electron tunneling indicate that electrical resistivity follows a universal curve with a scaling parameter. The scaling parameter is determined to be a measure of the fluctuations in the electron-hole puddle distribution.