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arXiv · 1308.6199

Fermi velocity renormalization and dynamical gap generation in graphene

C. Popovici·C. S. Fischer·L. von Smekal
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Abstract

We study the renormalization of the Fermi velocity by the long-range Coulomb interactions between the charge carriers in the Dirac-cone approximation for the effective low-energy description of the electronic excitations in graphene at half filling. Solving the coupled system of Dyson-Schwinger equations for the dressing functions in the corresponding fermion propagator with various approximations for the particle-hole polarization we observe that Fermi velocity renormalization effects generally lead to a considerable increase of the critical coupling for dynamical gap generation and charge-density wave formation at the semimetal-insulator transition.

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C. Popovici, C. S. Fischer, L. von Smekal. 2013-08-28. Fermi velocity renormalization and dynamical gap generation in graphene. https://doi.org/10.1103/physrevb.88.205429

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