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arXiv · cond-mat/9809187

d-wave superconductivity in a generalized Hubbard model

Liliana Arrachea·A. A. Aligia
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Abstract

We consider an extended Hubbard model with nearest-neighbor correlated hopping and next nearest-neighbor hopping t' obtained as an effective model for cuprate superconductors. Using a generalized Hartree-Fock BCS approximation, we find that for high enough t' and doping, antiferromagnetism is destroyed and the system exhibits d-wave superconductivity. Near optimal doping we consider the effect of antiferromagnetic spin fluctuations on the normal self-energy using a phenomenological susceptibility. The resulting superconducting critical temperature as a function of doping is in good agreement with experiment.

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Liliana Arrachea, A. A. Aligia. 1998-09-13. d-wave superconductivity in a generalized Hubbard model. https://doi.org/10.1103/physrevb.59.1333

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