Van Hove Singularity and Superconductivity in Disordered Hubbard Model
arXiv:cond-mat/0112470 · doi:10.1002/1521-3951(200202)229:3<1427::AID-PSSB1427>3.0.CO;2-0
Abstract
We apply the Coherent Potential Approximation (CPA) to a simple extended Hubbard model with a nearest and next nearest neighbour hopping for disordered superconductors with s-, d- and p-wave pairing. We show how the Van Hove singularities in the electron density of states enhance the transition temperature Tc for exotic superconductors in a clean and weakly disordered system. The Anderson theorem and pair-breaking effects in presence of Van Hove singularity caused by non-magnetic disorder are also discussed.
REVTEX 40 pages, 8 figures, (accepted by Physica Status Solidi b)