Quantum based RF E-field sensing by using two-photon transition in Rydberg atoms

It has been proved that quantum coherence effects in highly-excited Rydberg atoms could provide a revolutionary solution for RF field measurement. A two-photon transition due to interaction of RF electric field with cesium Rydberg atoms will be discussed. RF E-field whose carrier frequency satisfies a two-photon transition can induce an Autler-Townes splitting within electromagnetically induced transparency (EIT) spectroscopy, and the field strength is directly linked to the measured energy splitting and Planck's constant. Proof-of-concept measurement results will be presented, which also indicate the possibility of sub-wavelength sensing. This work is of major significance for developing quantum-based RF field metrology.