Simulation study on the mechanical tuning of high-Tc superconducting microwave filters

We tried to apply the mechanical tuning method to lumped-element superconducting filters and investigated the tunability by simulation. This tuning method is the same as we previously adopted for tuning microstrip-line-type resonators, i.e., tuning by the displacement of a dielectric floating plate with an actuator above the resonator. We considered band pass filters with a center frequency in a GHz range and a bandwidth of a few tens to a few hundreds MHz. The inductors and the capacitors were designed and simulated using an electromagnetic analysis simulator, Sonnet EM. We assumed MgO for the substrate and the floating plate. We investigated the properties of the filters and their tunability.