Detection of 3–300 MHz electric fields using Floquet sideband gaps by “Rabi matching” dressed Rydberg atoms

Radio frequencies in high-frequency (HF) and very high-frequency (VHF) bands (3–300 MHz) are challenging for Rydberg atom-based detection schemes, as resonant detection requires exciting atoms to extremely high energy states. We demonstrate a method for detecting and measuring radio frequency carriers in these bands via a controlled Autler–Townes line splitting. Using a resonant 18 GHz field, the absorption signal from Townes–Merritt sidebands created by a relatively low-frequency, non-resonant field can be enhanced. Notably, this technique uses a measurement of optical frequency separation of an avoided crossing to determine the amplitude of a non-resonant field. This technique also provides frequency-selective measurements of electric fields in the hundreds of MHz range with resolution of order 10 MHz. To show this, we demonstrate amplitude-modulated signal transduction on a MHz-range carrier. We further demonstrate reception of multiple tones simultaneously, creating a Rydberg “spectrum analyzer.”