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arXiv · 2005.10591

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

Anderson L. R. Barbosa·Jonas R. F. Lima·Ícaro S. F. Bezerra·Marcelo L. Lyra
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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.

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Anderson L. R. Barbosa, Jonas R. F. Lima, Ícaro S. F. Bezerra, Marcelo L. Lyra. 2020-05-21. Electronic transport in disordered graphene superlattices with scale-free correlated barrier spacements. https://doi.org/10.1016/j.physe.2020.114210

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