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Superconductivity and incommensurate spin fluctuations in a generalized t-J model for the cuprates

C. D. Batista·L. O. Manuel·H. A. Ceccatto·A. A. Aligia
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Abstract

We consider the slave-fermion Schwinger-boson decomposition of an effective model obtained through a systematic low-energy reduction of the three-band Hubbard Hamiltonian. The model includes a three-site term t'' similar to that obtained in the large-U limit of the Hubbard model but of opposite sign for realistic or large O-O hopping. For parameters close to the most realistic ones for the cuprates, the mean-field solution exhibits d+s superconductivity (predominantly d_{x^2-y^2}) with a dependence on doping x very similar to the experimentally observed. We also obtained incommensurate peaks at wave vectors near $π(1,1 +(-) 2x)$ in the spin structure factor, which also agree with experiment.

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C. D. Batista, L. O. Manuel, H. A. Ceccatto, A. A. Aligia. 1997-03-14. Superconductivity and incommensurate spin fluctuations in a generalized t-J model for the cuprates. https://doi.org/10.1209/epl%2Fi1997-00216-4

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