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The low energy electronic band structure of bilayer graphene.

McCann, Edward and Abergel, David S. L. and Falko, Vladimir (2007) The low energy electronic band structure of bilayer graphene. European Physical Journal - Special Topics, 148 (1). pp. 91-103. ISSN 1951-6355

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    Abstract

    We employ the tight binding model to describe the electronic band structure of bilayer graphene and we explain how the optical absorption coefficient of a bilayer is influenced by the presence and dispersion of the electronic bands, in contrast to the featureless absorption coefficient of monolayer graphene. We show that the effective low energy Hamiltonian is dominated by chiral quasiparticles with a parabolic dispersion and Berry phase 2π. Layer asymmetry produces a gap in the spectrum but, by comparing the charging energy with the single particle energy, we demonstrate that an undoped, gapless bilayer is stable with respect to the spontaneous opening of a gap. Then, we describe the control of a gap in the presence of an external gate voltage. Finally, we take into account the influence of trigonal warping which produces a Lifshitz transition at very low energy, breaking the isoenergetic line about each valley into four pockets.

    Item Type: Article
    Journal or Publication Title: European Physical Journal - Special Topics
    Additional Information: The original publication is available at www.springerlink.com
    Subjects: Q Science > QC Physics
    Departments: Faculty of Science and Technology > Physics
    ID Code: 11375
    Deposited By: Dr Edward McCann
    Deposited On: 14 Aug 2008 09:48
    Refereed?: Yes
    Published?: Published
    Last Modified: 09 Apr 2014 20:19
    Identification Number:
    URI: http://eprints.lancs.ac.uk/id/eprint/11375

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