Microwave spectroscopy and Zeeman effect of cesium $(n+2)D_{5/2}\rightarrow nF_{J}$ Rydberg transitions

TL;DR

This study demonstrates high-resolution microwave spectroscopy of cesium Rydberg states, revealing Zeeman effects and coherent dynamics, with implications for quantum control and calibration in cold atom experiments.

Contribution

It provides detailed experimental and theoretical analysis of microwave-driven Rydberg transitions and Zeeman effects in cesium, advancing understanding of high-angular-momentum Rydberg states.

Findings

Observation of Fourier side-band spectra and Rabi oscillations.

Resolved Zeeman splitting patterns in magnetic fields.

Good agreement between experimental data and theoretical models.

Abstract

We report on high-resolution microwave spectroscopy of cesium Rydberg $(n+2)D_{5/2}\rightarrow nF_{J}$ transitions in a cold atomic gas. Atoms laser-cooled and trapped in a magnetic-optical trap are prepared in the $D$ Rydberg state using a two-photon laser excitation scheme. A microwave field transmitted into the chamber with a microwave horn drives the Rydberg transitions, which are probed via state selective field ionization. Varying duration and power of the microwave pulse, we observe Fourier side-band spectra as well as damped, on-resonant Rabi oscillations with pulse areas up to $\gtrsim 3 \pi$. Furthermore, we investigate the Zeeman effect of the clearly resolved $nF_J$ fine-structure levels in fields up to 120~mG, where the transition into $nF_{7/2}$ displays a thee-peak Zeeman pattern, while $nF_{5/2}$ shows a two-peak pattern. Our theoretical models explain all observed spectral characteristics, showing good agreement with the experiment. Our measurements provide a pathway for the study of high-angular-momentum Rydberg states, initialization and coherent manipulation of such states, Rydberg-atom macrodimers, and other Rydberg-atom interactions. Furthermore, the presented methods are suitable for calibration of microwave radiation as well as for nulling and calibration of DC magnetic fields in experimental chambers for cold atoms.