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arXiv · 2407.02154

Predicting correlations in superradiant emission from a cascaded quantum system

Felix Tebbenjohanns·Christopher D. Mink·Constanze Bach·Arno Rauschenbeutel·Michael Fleischhauer
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Abstract

In recent experiments, a novel type of cascaded quantum system has been realized using nanofiber-coupled cold atomic ensembles. This setup has enabled the study of superradiant decay of highly excited collective spin states of up to a thousand atoms, featuring unidirectional coupling mediated by the waveguide mode. The complexity arising from the large, multi-excited ensemble and the cascaded interactions between atoms makes conventional simulation methods unsuitable for predicting the correlations of superradiant emission beyond the first order. To address this challenge, we developed a new simulation technique based on the truncated Wigner approximation for spins. Our stochastic simulation tool can predict the second-order quantum coherence function, $g^{(2)}$, along with other correlators of the light field emitted by a strongly excited cascaded system of two-level emitters. This approach thus provides an effective and scalable method for analyzing cascaded quantum systems with large numbers of particles.

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Felix Tebbenjohanns, Christopher D. Mink, Constanze Bach, Arno Rauschenbeutel, Michael Fleischhauer. 2024-07-02. Predicting correlations in superradiant emission from a cascaded quantum system. https://doi.org/10.1103/physreva.110.043713

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