Conductance enhancement due to atomic potential fluctuations in graphene

TL;DR

This paper investigates how atomic potential fluctuations in graphene enhance conductance by analyzing a pseudospin-dependent scattering effect and tunneling conductance using the Dirac equation and transfer matrix approach.

Contribution

It introduces a novel pseudospin-dependent scattering effect in graphene and generalizes conductance calculations considering atomic potential fluctuations.

Findings

Atomic potential fluctuations increase graphene's conductance.

Absence of back scattering is linked to Berry's phase.

Analytical results are extended to tunable atomic potentials.

Abstract

We solve the Dirac equation, which describes charge massless chiral relativistic carriers in a two-dimensional graphene. We have identified and analysed a novel pseudospin-dependent scattering effect. We compute the tunneling conductance and generalize the analytical result in the presence of the tunable atomic potential of a graphene strip. The absence of back scattering in graphene is shown to be due to Berry's phase which corresponds to a sign change of the wave function under a spin rotation of a particle. We use the transfer matrix approach and find that the electric conductance of doped graphene increases due to atomic potential fluctuations.