Numerical optimization of hybrid dielectric/HTS resonators for surface impedance evaluation of HTS films

This work describes an alternative to the traditional dielectric resonator topology used for measuring surface impedance in High Temperature Supercond ucting (HTS) films. A gap is introduced above the dielectric so that only t he lower film is in direct contact with it. This arrangement has been used extensively for mechanical tuning of dielectric resonators and, when used f or surface impedance measurement, it can be designed to make the losses in the upper film small relative to the overall resonator losses. Then, measur ed results are mostly due to one of the films and not the average of two. T he specifics of a resonator design for measuring 2-inch wafers are presente d. An analysis and optimization of the resonator is done using a numericall y efficient mode-matching algorithm.