Resonant measurements of surface resistance of high-T-c superconducting films: How good or bad are they?

Errors in measurements of surface resistance R(s) of HTS materials are due to discrepancy between a mathematical model describing physical phenomena and a real measurement environment, finite accuracy of measurements of the e-factor, and finite accuracy of constants used for calculation of R(s). In this paper we analyze errors in R(s) due to uncertainties in the Q-factor, geometrical coefficients, loss tangent, R(sCu), and other factors when a cylindrical copper cavity with an HTS end plate, a stripline resonator, and sapphire rod resonators are used for HTS characterization.