Conductivity of a graphene strip: width and gate-voltage dependencies

TL;DR

This paper investigates how the width and gate voltage influence the electrical conductivity of graphene strips, revealing a significant size effect that enhances conductivity by up to 40% in narrow samples.

Contribution

It introduces a model accounting for edge charge accumulation and electrostatic effects, highlighting their impact on graphene conductivity in narrow strips.

Findings

Electrostatic size effect can increase conductivity by about 40%.

Edge charge accumulation significantly influences conductivity.

Size effects are crucial for device simulation and understanding scattering mechanisms.

Abstract

We study the conductivity of a graphene strip taking into account electrostatically-induced charge accumulation on its edges. Using a local dependency of the conductivity on the carrier concentration we find that the electrostatic size effect in doped graphene strip of the width of 0.5 - 3 $% \mu $m can result in a significant (about 40%) enhancement of the effective conductivity in comparison to the infinitely wide samples. This effect should be taken into account both in the device simulation as well as for verification of scattering mechanisms in graphene.