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arXiv · 0911.0558

The effect of sublattice symmetry breaking on the electronic properties of a doped graphene

Alireza Qaiumzadeh·Reza Asgari
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Abstract

Motivated by a number of recent experimental studies, we have carried out the microscopic calculation of the quasiparticle self-energy and spectral function in a doped graphene when a symmetry breaking of the sublattices is occurred. Our systematic study is based on the many-body G$_0$W approach that is established on the random phase approximation and on graphene's massive Dirac equation continuum model. We report extensive calculations of both the real and imaginary parts of the quasiparticle self-energy in the presence of a gap opening. We also present results for spectral function, renormalized Fermi velocity and band gap renormalization of massive Dirac Fermions over a broad range of electron densities. We further show that the mass generating in graphene washes out the plasmaron peak in spectral weight.

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Alireza Qaiumzadeh, Reza Asgari. 2009-11-03. The effect of sublattice symmetry breaking on the electronic properties of a doped graphene. https://doi.org/10.1088/1367-2630%2F11%2F9%2F095023

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