Van Hove Singularity and Superconductivity in Disordered Hubbard Model
نویسنده
چکیده
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. Pacs. 74.62.Dh, 74.20-z
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