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arXiv · 1012.4955

Two-dimensional Graphene with Structural Defects: Elastic Mean Free Path, Minimum Conductivity and Anderson Transition

Aurélien Lherbier·Simon M. -M. Dubois·Xavier Declerck·Stephan Roche·Yann-Michel Niquet·Jean-Christophe Charlier
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Abstract

Quantum transport properties of disordered graphene with structural defects (Stone-Wales and divacancies) are investigated using a realistic π-π* tight-binding model elaborated from ab initio calculations. Mean free paths and semiclassical conductivities are then computed as a function of the nature and density of defects (using an order-N real-space Kubo-Greenwood method). By increasing of the defect density, the decay of the semiclassical conductivities is predicted to saturate to a minimum value of 4e^2/πh over a large range (plateau) of carrier density (> 0.5 10^{14}cm^{-2}). Additionally, strong contributions of quantum interferences suggest that the Anderson localization regime could be experimentally measurable for a defect density as low as 1%.

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Aurélien Lherbier, Simon M. -M. Dubois, Xavier Declerck, Stephan Roche, Yann-Michel Niquet, Jean-Christophe Charlier. 2010-12-22. Two-dimensional Graphene with Structural Defects: Elastic Mean Free Path, Minimum Conductivity and Anderson Transition. https://doi.org/10.1103/physrevlett.106.046803

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