Microwave properties of YBCO/LAO and YBCO/MgO superconducting thin films

The microwave response of YBa₂Cu₃O₇/LaAlO₃ (YBCO/LAO) and YBa₂Cu₃O₇/MgO (YBCO/MgO) superconducting thin films was studied by microstrip resonator technique. Microwave characteristics of the superconducting films were analyzed by the temperature dependence of resonant frequency, load quality factor and insert loss. The penetration depth at 0 K can be attained as:λ₀=265 nm for YBCO/LAO and λ₀=280 nm for YBCO/MgO. The microwave surface resistance Rs of YBCO/LAO and YBCO/MgO was also investigated by microstrip resonator.