Highly-selective electronically-tunable cryogenic filters using monolithic, discretely-switchable MEMS capacitor arrays

A low loss electronically tunable filter was demonstrated using HTS/Au MEMS switched capacitor arrays. The two-pole filter was tuned by simultaneously varying the capacitance of each resonator by equal amounts. A K factor of between 3,500 and 5,000 was demonstrated for single pole resonators. The total tuning range was about 25% with an average Q of 7,000 at 77 K.