Tunable Sensitivity Enhancement of a Rydberg-Atom Electrometer

This paper presents a metallic resonant cavity for sensitivity enhancement of a Rydberg atom microwave electrometer. The Rubidium-filled vapor cell is encased by the resonator, with appropriate coupling structures for laser beams and the incident radio-frequency field. The resonator is designed to enhance the sensitivity of Rydberg states from 10.19 to 10.77GHz with 620MHz of frequency tunability. The resonator exhibits an intrinsic Q-factor ranging from 4546 to 5520, for ultimate field enhancement factors ranging from 3.5 to 9.3.