Effect of the long-range Coulomb interaction on phase diagram of the Kohn-Luttinger superconducting state in idealized graphene

Abstract

The effect of the long-range Coulomb interaction on the realization of the Kohn-Luttinger superconductivity in idealized monolayer doped graphene is studied. It is shown that the allowance for the Kohn-Luttinger renormalizations up to the second order in perturbation theory in the on-site Hubbard interaction inclusively, as well as the intersite Coulomb interaction significantly affects the competition between the superconducting phases with the $f$-wave, $p+ip$-wave and $d+id$-wave symmetries of the order parameter. It is shown that the account for the Coulomb repulsion of electrons located at the next-nearest neighboring atoms in such a system changes qualitatively the phase diagram and enhances the critical superconducting temperature.

6 pages, 3 figures. Submitted to the Special Issue of "Journal of Low Temperature Physics" "Recent Progress in Low Temperature Physics - NT37"