s+d MIXING IN CUPRATES: Strong electron correlations and superconducting gap symmetry

摘要

A microscopical theory of electronic spectrum and superconductivity is for- mulated within the two-dimensional anisotropic t-J model with t_x ≠ t_y and J_x ≠ J_y. The Dyson equation is solved in the weak coup ing approximation. The superconducting pairing mediated by spin-fluctuations has d+s symmetry with the s+component being proportional to the asymmetry |t_x ― t_y|.