Power handling of high temperature superconductors measured in an HTS/Sapphire resonator: A power reference film

The power handling of HTS thin films was accurately characterized in an 8.15 GHz HTS/Sapphire resonator as a function of temperature. The surface resistance of a superconductor depends upon the level of the surface magnetic field especially if the value exceeds the lower critical magnetic field. A four-film power round robin was performed, which allowed for both the power handling of each of the HTS films and the statistics about the measurement repeatability to be calculated. A highly nonlinear empirically derived formula was identified and used to interpolate the measurement data. These four HTS films can now be used as power-qualified reference films for future HTS/Sapphire resonator measurements.