The many-body correction to the band structure of a quasi-free-standing graphene layer is obtained within the Overhauser approach, where the electron-plasmon interaction is described as a field theoretical problem. We find that the Dirac-like spectrum is shifted by $\Delta E(\mathbf{k}=0)$, which is on the order of 50–150 meV, depending on the electron concentration $n_e$, and is in semiquantitative agreement with experimental data. The value of the Fermi velocity is renormalized by several percents and decreases with increasing electron concentration as found experimentally.

• Received 27 February 2012

DOI:https://doi.org/10.1103/PhysRevB.85.205454