Multichannel, ultra-wideband Rydberg electrometry with an optical frequency comb

While Rydberg atoms have shown tremendous potential to serve as accurate and sensitive detectors of microwaves and millimeter waves, their response is generally limited to a single, narrow frequency band around a chosen transition. As a result, their potential to serve as agile and wideband electromagnetic receivers has not been fully realized. Here we demonstrate the use of a mid-infrared, frequency agile optical frequency comb as the coupling laser for three-photon Rydberg atom electrometry. This approach allows for rapid switching between as many as seven individual Rydberg states, allowing for multichannel detection across a frequency range from 1 GHz to 40 GHz. The generality and flexibility of this method for wideband multiplexing is anticipated to have transformative effects in the field of Rydberg electrometry, paving the way for advanced information coding, arbitrary signal detection, and the simultaneous detection of ultra-broadband radiofrequency radiation.