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arXiv · 1311.7546

Conductivity of Graphene with Resonant Adsorbates: Beyond the Nearest Neighbor Hopping Model

Abstract

Adsorbates on graphene can create resonances that lead to efficient electron scattering and strongly affect the electronic conductivity. Therefore a proper description of these resonances is important to get a good insight of their effect on conductivity. The characteristics of the resonance and in particular its T-matrix depend on the adsorbate itself but also on the electronic structure of graphene. Here we show that a proper tight-binding model of graphene which includes hopping beyond the nearest-neighbor lead to sizable modifications of the scattering properties with respect to the mostly used nearest neighbor hopping model. We compare results obtained with hopping beyond the nearest-neighbor to those of our recent work Phys. Rev. Lett. 113, 146601 (2013). We conclude that the universal properties discussed in our recent work are unchanged but that a detailed comparison with experiments require a sufficiently precise tight-binding model of the graphene layer.

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Guy Trambly de Laissardière, Didier Mayou. 2014-01-06. Conductivity of Graphene with Resonant Adsorbates: Beyond the Nearest Neighbor Hopping Model. https://doi.org/10.1088/2043-6262%2F5%2F1%2F015007

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