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arXiv · 1511.00377

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

M. Yu. Kagan·V. A. Mitskan·M. M. Korovushkin
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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.

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M. Yu. Kagan, V. A. Mitskan, M. M. Korovushkin. 2016-02-01. Effect of the long-range Coulomb interaction on phase diagram of the Kohn-Luttinger superconducting state in idealized graphene. https://doi.org/10.1007/s10909-015-1427-2

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