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arXiv · cond-mat/0112470

Van Hove Singularity and Superconductivity in Disordered Hubbard Model

G. Litak
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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.

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G. Litak. 2001-12-27. Van Hove Singularity and Superconductivity in Disordered Hubbard Model. https://doi.org/10.1002/1521-3951(200202)229%3A3%3C1427%3A%3Aaid-pssb1427%3E3.0.co%3B2-0

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