A high inductance kHz resonator with a quality factor larger than 106

Abstract
Electrical LC resonators with superconducting coils of ≊3.5 H inductance, operating in the frequency range 250–1500 Hz with quality factors up to Q≊1.6×106 are presented here. The coil has a reduced, <100 pF, stray capacitance and is housed in a superconducting case. Measurements are made with a low coupling SQUID readout. Some possible applications of the device are briefly discussed.