Doped graphene as a superconductor

We study s-wave superconductivity state in doped graphene within the extended attractive Hubbard model and BCS theory. We use the Green's function approach and coherent potential approximation. We obtain critical temperature of graphene, TcTc, as a function of the impurity concentration, c, as well as impurity strength, δ. The results show that when c and δ  , are increased, TcTc remains finite and doped graphene can be a superconductor.