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Superconductivity in the Extended Hubbard Model with More Than Nearest-Neighbour Contributions

Zs. Szabo·Zs. Gulacsi
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Abstract

Superconducting phase diagram of the extended Hubbard model supplemented with interaction and hopping terms exceeding nearest neighbour distance in range is analysed systematically at different band-filling and temperature values in a mean-field approximation. The obtained results clearly underline the importance of next-nearest neighbour terms in developing the main superconducting properties of the model system. In particular, the emergence of superconducting phases of different symmetry at a given point of the phase diagram, critical temperatures $T_c$, zero temperature gap amplitude values $Δ_{0}$, $Δ_{0}/T_{c}$ ratios, doping and temperature dependences are all strongly influenced by next-nearest neighbour contributions.

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Zs. Szabo, Zs. Gulacsi. 1998-08-25. Superconductivity in the Extended Hubbard Model with More Than Nearest-Neighbour Contributions. https://arxiv.org/abs/cond-mat/9808279

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