ON WGM RESONATOR TECHNIQUE FOR MICROWAVE CHARACTERIZATION OF SUPERCONDUCTORS IN NORMAL STATE

The paper presents preliminary results on the analysis of the applicability of microwave measurement techniques for study the properties of superconductors in normal state using dielectric resonators excited with whispering gallery modes (WGM). The expressions for microwave surface impedance for a normal conductor are derived. The experimental technique for measuring the surface impedance of superconductors in a normal state using mm-wave sapphire WGM resonator is proposed and described. The reliability of the proposed approach is demonstrated measuring the response of a resonator with copper samples is presented.