FREQUENCY DISPERSION OF HTSC-FILM IMPEDANCE IN THE MHZ RANGE

The impedance of a circuit including an HTSC film as a function of tem perature and frequency has been measured, and the presence of an intri nsic reactance in the HTSC films has been shown. The equivalent scheme of the measuring circuit has been synthesized, and the temperature de pendence, type, and value of the HTSC-film reactance has been determin ed in the transition region near T(c). It is shown that the change of reactance sign with temperature observed earlier by a number of resear chers and attributed to the intrinsic property of HTSC-film reactance was rather the result of the T-independent parasite reactive elements while the film impedance was becoming small.