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arXiv · 1109.6439

Metal-to-insulator transition and electron-hole puddle formation in disordered graphene nanoribbons

Gerald Schubert·Holger Fehske
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Abstract

The experimentally observed metal-to-insulator transition in hydrogenated graphene is numerically confirmed for actual sized graphene samples and realistic impurity concentrations. The eigenstates of our tight-binding model with substitutional disorder corroborate the formation of electron-hole-puddles with characteristic length scales comparable to the ones found in experiments. The puddles cause charge inhomogeneities and tend to suppress Anderson localization. Even though, monitoring the charge carrier quantum dynamics and performing a finite-size scaling of the local density of states distribution, we find strong evidence for the existence of localized states in graphene nanoribbons with short-range but also correlated long-range disorder.

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Gerald Schubert, Holger Fehske. 2011-12-17. Metal-to-insulator transition and electron-hole puddle formation in disordered graphene nanoribbons. https://doi.org/10.1103/physrevlett.108.066402

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