Microwave loss and intermodulation in Tl(2)Ba(2)CaCu(2)O(y) thin films

A superconducting microstrip hairpin resonator is used as a tool to study the linear and nonlinear microwave response of TBCCO thin films. We extract the surface resistance R(S)(T), penetration depth lambda(T), and intermodulation critical current J(IMD)(T) for such a resonator at 4.2 GHz. The surface impedance results compare well with cavity perturbation measurements on portions of the same wafer. J(IMD)(T) is compared against theoretical models for the intrinsic nonlinear response of s- and d-wave superconductors. We demonstrate that the de critical current J(c) and J(IMD) are distinct material parameters, describing different physical regimes.