2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/26975In superconductors where the coherence length is comparable to the Fermi wavelength, the electronic levels within a vortex core are quantized, and separated by energies of the order of the superconducting gap. The absence of a continuum modifies significantly the energy dissipation due to the motion of vortices. At zero temperature, dissipation is suppressed, and the system shows non ohmic behavior. The I-V characteristics show two distinct regimes. Below a given electric field, I is strongly dependent on V. Flux flow resistivity also shows a marked dependence on temperature, and reaches conventional values near $T_c$.8 pages (RevTex). 1 figure by resquestCondensed Mattertext