Power handling capability and intermodulation distortion of high-T_c microwave resonators

摘要

The nonlinearity of the microwave properties of coplanar thin-film YBa_2Cu_3O_(7-δ) resonators are examined by measurements of the degradation of the quality factor Q_L and the increase of the two-tone third-order intermodulation distortion signal with increasing microwave power. A linear correlation between the data of the characteristic microwave powers, which are obtained for the degradation of Q_L and the intermodulation signal, is experimentally observed and explained in terms of a theoretical model. Due to the experimental observation and the theoretical model, we conclude, that (ⅰ) the degradation of the resonator Q factor and the generation of intermodulation distortion are determined by the same physical mechanism and that (ⅱ) thermal effects can most likely be excluded.