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


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… (More)