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arXiv · 0710.3034

Effect of electron-electron interaction on the Fermi surface topology of doped graphene

R. Roldan·M. P. Lopez-Sancho·F. Guinea
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Abstract

The electron-electron interactions effects on the shape of the Fermi surface of doped graphene are investigated. The actual discrete nature of the lattice is fully taken into account. A $π$-band tight-binding model, with nearest-neighbor hopping integrals, is considered. We calculate the self-energy corrections at zero temperature. Long and short range Coulomb interactions are included. The exchange self-energy corrections for graphene preserve the trigonal warping of the Fermi surface topology, although rounding the triangular shape. The band velocity is renormalized to higher value. Corrections induced by a local Coulomb interaction, calculated by second order perturbation theory, do deform anisotropically the Fermi surface shape. Results are compared to experimental observations and to other theoretical results.

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R. Roldan, M. P. Lopez-Sancho, F. Guinea. 2008-03-14. Effect of electron-electron interaction on the Fermi surface topology of doped graphene. https://doi.org/10.1103/physrevb.77.115410

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