Abstract: The electric field measurement based on Rydberg atoms, due to its high sensitivity, large dynamic range, and broad spectral coverage, has broad application prospects in fields such as information communication, spectrum detection, and meteorological warning, and is expected to become one of the key technologies for next-generation electromagnetic spectrum sensing. With ongoing advancements in both theory and experiment, the sensitivity of electric field measurement based on Rydberg atoms is gradually approaching the quantum projection noise limit. This article outlines the principles of electric field measurement based on Rydberg atoms, and reviews the recent progress in both single-body and many-body electric field measurement based on Rydberg atoms. So far, researchers have continually optimized electric field measurement techniques based on electromagnetically induced transparency and Autler-Townes (AT) splitting, employing methods such as the homodyne detection technique, superheterodyne technique, repumping, and six-wave mixing. These approaches have improved the electric field measurement sensitivity of single-body systems to 3.98 nV·cm−1 ·Hz−1/2 , and the phase measurement sensitivity to 2 mrad. In addition to single-body systems, many-body systems based on Rydberg atoms have also been widely applied in electric field measurements by using their criticality at the phase trasition point, and the measurement sensitivity in many-body systems is expressed using Fisher information. Techniques such as cavity-enhanced optical bistability and stochastic resonance enhancement have been employed in many-body electric field measurement, and recent studies demonstrate that a 6.6 dB improvement in electric field measurement sensitivity, as well as robust resistance to external noise, has been achieved.

Key words: quantum optics, electric field measurement, electromagnetically induced transparency, Rydberg atom, many-body systems