Electronic Transport in Dual-gated Bilayer Graphene at Large Displacement Fields

TL;DR

This study investigates the electronic transport in dual-gated bilayer graphene under large displacement fields, revealing exponential resistance dependence, non-linear transport behavior, and a smaller effective transport gap compared to optical measurements.

Contribution

It provides new insights into transport mechanisms and the effective transport gap in bilayer graphene at high displacement fields and low temperatures.

Findings

Resistance shows exponential dependence on displacement field and density.

Transport gap is much smaller than optical band gaps.

Different transport mechanisms are active at various temperature regimes.

Abstract

We study the electronic transport properties of dual-gated bilayer graphene devices. We focus on the regime of low temperatures and high electric displacement fields, where we observe a clear exponential dependence of the resistance as a function of displacement field and density, accompanied by a strong non-linear behavior in the transport characteristics. The effective transport gap is typically two orders of magnitude smaller than the optical band gaps reported by infrared spectroscopy studies. Detailed temperature dependence measurements shed light on the different transport mechanisms in different temperature regimes.