Marginal-Fermi-liquid behavior from two-dimensional Coulomb interaction

A full, nonperturbative renormalization group analysis of interacting electrons in a graphite layer is performed, in order to investigate the deviations from Fermi-liquid theory that have been observed in the experimental measures of a linear quasiparticle decay rate in graphite. The electrons are coupled through Coulomb interactions, which remain unscreened due to the semimetallic character of the layer. We show that the model flows towards the noninteracting fixed point for the whole range of couplings, with logarithmic corrections which signal the marginal character of the interaction separating Fermi-liquid and non-Fermi-liquid regimes.