Microwave and millimeter wave characterization of high temperature superconducting thin films

Stripline transmission line resonators and resonant cavities were used to determine the surface resistance of high-T/sub c/ superconducting materials and were found to be an effective measurement tool. Thin films were found to have surface resistivity values slightly better than those of cooled copper at 20 K in the frequency range from 3 to 26 GHz, while the more nearly single-crystal bulk samples had even lower surface resistivity values in the millimeter-wave frequency range.<
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