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Ab Initio Theory of Gate Induced Gaps in Graphene Bilayers

Hongki Min·B. R. Sahu·Sanjay K. Banerjee·A. H. MacDonald
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Abstract

We study the gate voltage induced gap that occurs in graphene bilayers using \textit{ab initio} density functional theory. Our calculations confirm the qualitative picture suggested by phenomenological tight-binding and continuum models. We discuss enhanced screening of the external interlayer potential at small gate voltages, which is more pronounced in the \textit{ab initio} calculations, and quantify the role of crystalline inhomogeneity using a tight-binding model self-consistent Hartree calculation.

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Hongki Min, B. R. Sahu, Sanjay K. Banerjee, A. H. MacDonald. 2007-04-26. Ab Initio Theory of Gate Induced Gaps in Graphene Bilayers. https://doi.org/10.1103/physrevb.75.155115

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