Nonlinear characteristics of HTS planar resonators and filters

A phenomenological model of nonlinear characteristics of high-T(c), superconducting resonators is developed as applied to microstrip and coplanar waveguide resonators, coupled microstrip lines resonator, and planar transmission line filter. The following characteristics can be obtained as the nonlinear response: the unloaded Q-factor, the insertion loss in a frequency band (resonant characteristic), and the intermodulation distortion characteristic (third order intercept). The model was experimentally verified on YBCO microstrip and coplanar waveguide resonators manufactured on r-cut sapphire substrate. A good agreement was observed between simulated and measured data.