An improved dielectric resonator method for surface impedance measurement of high-T/sub c/ superconductors

An improved dielectric resonator method is proposed to measure the temperature characteristics of the surface impedance Z/sub s/ of superconductors automatically and with high resolution and good reproducibility. A perturbation formula for this resonator is derived to determine Z/sub s/ from measured values of resonant frequency and unloaded Q. Some measured results verified the usefulness of this method. A consideration of the effect of surface roughness was used to compare measured temperature dependence of the complex conductivity with the BCS model and three-fluid models.<
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