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arXiv · 1607.02935

On the Coulomb interaction in superconducting pairing in cuprates

N. Plakida
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Abstract

We discuss a reduction of superconducting transition temperature by the intersite Coulomb repulsion for the d-wave pairing in cuprates. We compare the results found for the spin-fermion model and the extended Hubbard model. We argue that in both the models the d-wave superconducting transition temperature is reduced by the Coulomb repulsion of holes in different unit cells. We also show that in the strong correlation limit the s-wave superconductivity cannot occur due to the kinematic restriction of no double occupancy in the Hubbard subbands.

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N. Plakida. 2016-07-11. On the Coulomb interaction in superconducting pairing in cuprates. https://arxiv.org/abs/1607.02935

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