The developing frequency-comb spectral technologies have potential applications and prospects in the wide fields of cosmology, meteorology, and microwave measurement. Here, we demonstrate a Rydberg microwave-frequency-comb spectrometer via multiple-microwave field dressing, providing precise microwave measurement. The Rydberg microwave-frequency-comb spectrum provides a real-time and absolute-frequency measurement with a range of 125 MHz and gives the relative phase of a single-frequency microwave signal. The reported experiment helps real-time sensing of an unknown microwave signal over a wide range using Rydberg atoms, which are vital for Rydberg-atom-based microwave metrology.

• Received 8 October 2021
• Revised 5 May 2022
• Accepted 13 June 2022

DOI:https://doi.org/10.1103/PhysRevApplied.18.014033