Electronic transport in disordered graphene superlattices with scale-free correlated barrier spacements

TL;DR

This study investigates how long-range correlated disorder in barrier spacements affects electronic transport in graphene superlattices, revealing suppression of Anderson localization and the emergence of transmitting modes akin to Klein tunneling.

Contribution

It introduces a transfer matrix analysis of graphene superlattices with scale-free correlated barriers, highlighting the impact of disorder correlations on electron transmission.

Findings

Correlations do not significantly affect transmission at large angles.

Long-range correlations suppress Anderson localization near normal incidence.

A band of transmitting modes emerges, similar to Klein tunneling.

Abstract

A transfer matrix approach is used to study the electronic transport in graphene superlattices with long-range correlated barrier spacements. By considering the low-energy electronic excitations as massless Dirac fermions, we compute by transmission spectra of graphene superlattices with potential barriers having spacements randomly distributed with long-range correlations governed by a power-law spectral density $S(k)\propto 1/k^{\alpha}$. We show that at large incidence angles, the correlations in the disorder distribution do not play a significant role in the electronic transmission. However, long-range correlations suppress the Anderson localization as normal incidence is approached and a band of transmitting modes sets up reminiscent of Klein tunneling.