Real-time detection of Rydberg state dynamics of cold atoms using an optical cavity

TL;DR

This paper demonstrates real-time detection of Rydberg state dynamics in cold atoms using an optical cavity, revealing superradiant effects and interactions that advance understanding of Rydberg atom behavior.

Contribution

It introduces a method for real-time monitoring of Rydberg state dynamics in cold atoms via cavity transmission, highlighting superradiance and dipole interactions.

Findings

Detection of superradiant enhancement in Rydberg transitions

Observation of density-dependent mitigation of superradiance

Insights into the interplay between BBR-induced superradiance and Rydberg interactions

Abstract

This work reports on the real-time detection of internal-state dynamics of cold Rb$^{87}$ atoms being excited to the $30D_{5/2}$ Rydberg state via two-photon excitation. A mesoscopic cloud of atoms is overlapped with the mode volume of a confocal optical cavity and optically pumped by two laser beams transverse to the cavity axis. The excitation to Rydberg states changes the collective atom-cavity coupling, which is detected by monitoring the light transmitted through the cavity while being weakly driven. In addition to the damped coherent excitation dynamics and the decay back to the ground state, the data show a superradiant enhancement of the black-body radiation induced transitions from the $30D_{5/2}$ state to neighboring Rydberg states. Furthermore, they show a density dependent mitigation of the superradiant decay which is attributed to long range dipole-dipole interactions between atoms in the involved Rydberg states. These results contribute to solving a recent controversy on the interplay between BBR-induced superradiance and Rydberg atom interactions.