Graphene-based ferromagnetic superconductors

We propose a graphene-based model for realizing a special type of gapless condensate by pairing of electron-like (n) carriers of a Dirac cone conduction band with hole-like (p) carriers of a Dirac valance band. This condensate can be realized by ferromagnetic superconductivity in monolayer graphene. The p-n condensate dominates the zero temperature phase diagram at low levels of doping and high exchange fields. We find that p-n pairing with p+ip-wave symmetry presents a stable condensate phase, which can cover the phase diagram up to surprisingly strong exchange fields. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4772507]