2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/123723A phenomenological description of the high-Tc superconductors based on the Cooperon propagator is presented. This model allows one to study the effects of local pairing correlations and long-range phase fluctuations on the same footing, both above and below Tc. Based on numerical calculations, it is shown that the two types of correlations contribute to the gap/pseudogap in the single-particle excitation spectra. The concourse of these two effects can induce low energy states, which should be observable in underdoped materials at very low temperature.LaTeX, 6 pages, 2 EPS figures; paper presented at New^3SC-3, Hawaii, 01/2001. To appear in Physica CSuperconductivitytext