Quasiparticles and c-axis coherent hopping in high-T-c superconductors - art. no. 060504

We study the problem of the low-energy quasiparticle spectrum of the extend ed t-J model and analyze the coherent hopping between weakly coupled planes described by this model. Starting with a two-band model describing the CuO planes and the unoccupied bands associated with the metallic atoms located in between the planes, we obtain effective hopping matrix elements describ ing the c-axis charge transfer. A computational study of these processes sh ows an anomalously large charge anisotropy for doping concentrations around and below the optimal doping.