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arXiv · 0905.2766

Gaps and tails in graphene and graphane

B. Dora·K. Ziegler
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Abstract

We study the density of states in monolayer and bilayer graphene in the presence of a random potential that breaks sublattice symmetries. While a uniform symmetry-breaking potential opens a uniform gap, a random symmetry-breaking potential also creates tails in the density of states. The latter can close the gap again, preventing the system to become an insulator. However, for a sufficiently large gap the tails contain localized states with nonzero density of states. These localized states allow the system to conduct at nonzero temperature via variable-range hopping. This result is in agreement with recent experimental observations in graphane by Elias {\it et al.}.

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B. Dora, K. Ziegler. 2009-05-17. Gaps and tails in graphene and graphane. https://doi.org/10.1088/1367-2630%2F11%2F9%2F095006

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