Loss rates for high-$n$, $49\lesssim n \lesssim150$, 5sns($^{3}$S$_{1}$) Rydberg atoms excited in an $^{84}$Sr Bose-Einstein condensate

TL;DR

This study measures loss rates of high-n strontium Rydberg atoms in a Bose-Einstein condensate, identifying dominant loss mechanisms and comparing results with rubidium, revealing significant loss rates that impact quantum gas experiments.

Contribution

First detailed measurement of loss rates for high-n strontium Rydberg atoms in a dense BEC, analyzing loss channels and their dependencies, and comparing with rubidium results.

Findings

Loss rates are around 10^5 to 10^6 s^-1.

Associative ionization and state-changing are main loss processes.

Loss rates limit measurement times in quantum gas experiments.

Abstract

Measurements of the loss rates for strontium n$^{3}$S$_{1}$ Rydberg atoms excited in a dense BEC are presented for values of principal quantum number $n$ in the range $49\lesssim n \lesssim 150$ and local atom densities of $\sim1$ to $3\times10^{14}$cm$^{-3}$. Two main processes contribute to loss, associative ionization and state-changing. The relative importance of these two loss channels is investigated and their $n$- and density-dependences are discussed using a model in which Rydberg atom loss is presumed to involve a close collision between the Rydberg core ion and ground-state atoms. The present measurements are compared to earlier results obtained using rubidium Rydberg atoms. For both species the observed loss rates are sizable, $\sim10^{5}-10^{6}$s$^{-1}$, and limit the time scales over which measurements involving Rydberg atoms immersed in quantum degenerate gases can be conducted.