A tunable filter having a fixed substrate, a first and second plate
comprising a high-temperature superconductor material on the fixed
substrate, a movable substrate, a mechanical driver attached to the fixed
substrate and the movable substrate, a floating plate comprising a
high-temperature superconductor material on the fixed substrate wherein
the floating plate, the first plate, and the second plate define a gap,
and wherein the gap is varied by length changes in the mechanical driver
is provided.