Fluctuative conducitivity at microwave frequencies in BSCCO thin films

Measurements of the real part of the resistivity at 23 and 48 GHz are perfo rmed in Bi2Sr2CaCu2O8+x thin films as a function of the temperature. The ex perimental behavior above Tc is analyzed in the frame of the time dependent Ginzburg-Landau theory for the excess conductivity. We show that the obser ved resistivity can be interpreted by the 2D gaussian theory due to the hig h anisotropy of tills compound. The validity of the theory is extended up t o the high temperature region with the introduction of a phenomenogical cut -off on the order parameter spectrum. Approaching T-c, data deport from the predicted behavior; this departure can be ascribed either to a dimensional crossover or to the effects of interacting fluctuations.