Measurement of the quantum defects of 85Rb P and F-series via microwave-assisted electromagnetically induced transparency spectroscopy

We report the measurement of the quantum defects of Rb-85 P-3/2 and F-7/2-series Rydberg levels in a room temperature vapor cell by microwave-assisted electromagnetically induced transparency (EIT) spectroscopy. First, a novel microwave optical three-photon excitation method is employed to obtain the microwave-assisted EIT spectroscopy of the 5S(1/2) - 5P(3/2) - nD(5/2) - (n+1)P-3/2 or (n-1)F-7/2 transition. Next, the Stark shifts of the corresponding Rydberg states relative to the Rabi frequency of microwave field are measured with high accuracy. Finally, the quantum defects, delta(0) = 2.64142(15), delta(2) = 0.295 for P-3/2-series, and delta(0) = 0.016411(16), delta(2) = -0.0784 for F-7/2-series, are forcibly extracted by the modified Rydberg-Ritz formula. This result can serve as a check on advanced theoretical calculations and promote the application of quantum simulations and quantum sensors in atomic ensembles.

Automated summary

We measured the quantum defects of Rb-85 P-3/2 and F-7/2-series Rydberg levels in a room temperature vapor cell using microwave-assisted EIT spectroscopy, obtaining accurate results through a novel microwave optical three-photon excitation method and measurements of Stark shifts. Forced extraction of quantum defects was done using a modified Rydberg-Ritz formula, providing a check on advanced theoretical calculations and promoting the application of quantum simulations and sensors.