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arXiv · 1711.09381

Spectral approach to transport in the 2D honeycomb lattice with substitutional disorder

E G Kostadinova·C D Liaw·A S Hering·A Cameron·F Guyton·L S Matthews·T W Hyde
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Abstract

The transport properties of a disordered two-dimensional (2D) honeycomb lattice are examined numerically using the spectral approach to the quantum percolation problem, characterized by an Anderson-type Hamiltonian. In our simulations, substitutional disorder (or doping) is represented by a modified bimodal probability distribution of the on-site energies. The results indicate the existence of extended energy states for nonzero disorder and the emergence of a transition towards localized behavior for critical doping concentration n_D>0.3%, in agreement with the experimentally observed metal-to-insulator transition in graphene sheet doped with hydrogen.

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E G Kostadinova, C D Liaw, A S Hering, A Cameron, F Guyton, L S Matthews, T W Hyde. 2018-08-03. Spectral approach to transport in the 2D honeycomb lattice with substitutional disorder. https://doi.org/10.1103/physrevb.99.024115

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