RF power dependence of microstrip disk resonators with YBCO films for 4 GHz band

High-Tc superconducting (HTS) power filters have an attractive possibility of being applied to the base stations of the- future mobile-communication systems. In the microstrip structure, disk-shape-patterned HTS resonators are considered potential candidates for the HTS power filters. In order to research the application feasibility of disk resonators, the resonator samples were fabricated with different quality YBCO thin-films, and the power handling and third intermodulation-distortion (IMD3) of the samples were then examined for the incident continuous wave power of up to about 10 W around 4 GHz at cryogenic temperatures. We discuss the results on the relationship between the RF power dependence and the YBCO film qualities.