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arXiv · 1110.5652

Universal conductance fluctuations in Dirac materials in the presence of long-range disorder

E. Rossi·J. H. Bardarson·M. S. Fuhrer·S. Das Sarma
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Abstract

We study quantum transport in Dirac materials with a single fermionic Dirac cone (strong topological insulators and graphene in the absence of intervalley coupling) in the presence of non-Gaussian long-range disorder. We show, by directly calculating numerically the conductance fluctuations, that in the limit of very large system size and disorder strength, quantum transport becomes universal. However, a systematic deviation away from universality is obtained for realistic system parameters. By comparing our results to existing experimental data on 1/f noise, we suggest that many of the graphene samples studied to date are in a non-universal crossover regime of conductance fluctuations.

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E. Rossi, J. H. Bardarson, M. S. Fuhrer, S. Das Sarma. 2012-09-03. Universal conductance fluctuations in Dirac materials in the presence of long-range disorder. https://doi.org/10.1103/physrevlett.109.096801

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