High Frequency Characterization of High Temperature Superconducting Thin-Film Lines

ABSTRACT An integral equation approach is applied to calculate the propagation characteristics of high temperature thin-film superconducting lines at high frequencies. To evaluate losses in these lines, the superconducting strips are replaced by frequency-dependent surface impedance boundaries. The values of these surface impedances are measured experimentally by a TE01 cavity technique. Using this method, a parametric study is performed where phase and attenuation constants as well as characteristic impedance are evaluated as functions of frequency, temperature, permittivity and geometry of the structure.