Abstract
The dynamical generation of a fermion gap in graphene is studied at the infra-red Lorentz-invariant fixed point where the system is described by an effective relativistic-like field theory: reduced with four-component fermions ( for graphene), where photons are () dimensional and mediate a fully retarded interaction among ()-dimensional fermions. A correspondence between reduced and allows us to derive an exact gap equation for up to next-to-leading order. Our results show that a dynamical gap is generated for , where in the case or for where is such that and takes the values . The striking feature of these results is that they are in good agreement with values found in models with instantaneous Coulomb interaction (including lattice simulations). At the fixed point, , and the system is therefore in the semimetallic regime in accordance with experiments.
- Received 7 October 2016
DOI:https://doi.org/10.1103/PhysRevD.94.114010
© 2016 American Physical Society