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arXiv · 2103.04528

Rydberg blockade in an ultracold strontium gas revealed by two-photon excitation dynamics

Chang Qiao·Can-Zhu Tan·Julia Siegl·Fa-Chao Hu·Zhi-Jing Niu·Y. H. Jiang·Matthias Weidemüller·Bing Zhu
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Abstract

We demonstrate the interaction-induced blockade effect in an ultracold $^{88}$Sr gas via studying the time dynamics of a two-photon excitation to the triplet Rydberg series $5\mathrm{s}n\mathrm{s}\, ^3\textrm{S}_1$ for five different principle quantum numbers $n$ ranging from 19 to 37. By using a multi-pulse excitation sequence to increase the detection sensitivity we could identify Rydberg-excitation-induced atom losses as low as $<1\%$. Based on an optical Bloch equation formalism, treating the Rydberg-Rydberg interaction on a mean-field level, the van der Waals coefficients are extracted from the observed dynamics, which agree fairly well with \emph{ab initio} calculations.

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Chang Qiao, Can-Zhu Tan, Julia Siegl, Fa-Chao Hu, Zhi-Jing Niu, Y. H. Jiang, Matthias Weidemüller, Bing Zhu. 2021-03-08. Rydberg blockade in an ultracold strontium gas revealed by two-photon excitation dynamics. https://doi.org/10.1103/physreva.103.063313

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