Bose-Einstein condensate-mediated BCS-like superconductivity in graphene
Meng Juan Sun, Anton V. Parafilo, Kristian Hauser A. Villegas, V. M. Kovalev, Ivan G. Savenko
Abstract
We propose a mechanism of robust BCS-like superconductivity in graphene placed in the vicinity of a Bose-Einstein condensate. Thus electrons in graphene interact with the excitations above the condensate, called the Bogoliubov quasiparticles (or bogolons). It turns out that bogolon-pair-mediated interaction allows us to surpass the long-standing problem of vanishing density of states of particles with a linear spectrum in the vicinity of the Dirac points. It results in a dramatic enhancement of the superconducting properties of graphene while keeping its relativistic dispersion. We study the behavior of the superconducting gap and calculate critical temperatures in the cases of single-bogolon and bogolon-pair-mediated pairing processes, accounting for the complex band structure of graphene. Surprisingly, both intravalley and intervalley bogolon-mediated pairings turn out equally possible.