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arXiv · cond-mat/9801035

Van Hove Singularity and D-Wave Pairing in Disordered Superconductors

G. Litak·A. M. Martin·B. L. Gyorffy·J. F. Annett·K. I. Wysokinski
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Abstract

We apply the coherent potential approximation (CPA) to a simple model for disordered superconductors with d-wave pairing. We demonstrate that whilst the effectiveness of an electronic Van Hove singularity to enhance the transition temperature T$_c$ is reduced by disorder it is not eliminated. In fact we give a qualitative account of changes in the T$_c$ vs. doping curve with increasing disorder and compare our results with experiments on the Y_{0.8}Ca_{0.2}Ba_2(Cu_{1-c}Zn_c)_{3}O_{7-δ} alloys.

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G. Litak, A. M. Martin, B. L. Gyorffy, J. F. Annett, K. I. Wysokinski. 1998-01-06. Van Hove Singularity and D-Wave Pairing in Disordered Superconductors. https://doi.org/10.1016/s0921-4534(98)00600-5

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