QUASI-PARTICLE BANDS AND SUPERCONDUCTIVITY FOR THE MULTIPLE-LAYER AND3-DIMENSIONAL SUPERLATTICE T-J MODELS

We present a propagator-matrix approach to calculate the one-hole spec trum for the multiple-layer and three-dimensional (3D) superlattice td models using the self-consistent Born approximation and then obtain t he superconducting transition temperature T-c within the antiferromagn etic van Hove scenario. The flat region around k(parallel to)(pi,0) in each band of the quasiparticle is observed for a trilayer and a 3D su perlattice with a bilayer per unit cell, while strong many-body effect s give rise to a large reduction of the band splitting. It is found th at for a trilayer the outer planes are slightly less doped than the in ner ones and for a 3D bilayer cuprate one can observe little dispersio n along k(z), in agreement with recent experimental data. Our calculat ions for rather different lattice structures and boundary conditions i ndicate that a large density of states leading to the boost of T-c mai nly results from the in-plane antiferromagnetic correlations rather th an from the band effects.