Rydberg excitation of Bose-Einstein condensates

TL;DR

This paper explores Rydberg excitation in Bose-Einstein condensates of 87Rb atoms, demonstrating how interactions influence excitation dynamics and the transition from thermal to condensed states.

Contribution

It presents the first detailed investigation of Rydberg excitation behavior in Bose-Einstein condensates, including experimental observations and a simulation model.

Findings

Rydberg excitation is locally blocked by van der Waals interactions.

The Rydberg fraction reflects the bimodal density distribution of the condensate.

Simulation accurately reproduces experimental Rydberg excitation features.

Abstract

Rydberg atoms provide a wide range of possibilities to tailor interactions in a quantum gas. Here we report on Rydberg excitation of Bose-Einstein condensed 87Rb atoms. The Rydberg fraction was investigated for various excitation times and temperatures above and below the condensation temperature. The excitation is locally blocked by the van der Waals interaction between Rydberg atoms to a density-dependent limit. Therefore the abrupt change of the thermal atomic density distribution to the characteristic bimodal distribution upon condensation could be observed in the Rydberg fraction. The observed features are reproduced by a simulation based on local collective Rydberg excitations.