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arXiv · 1806.00062

Observation of three-body correlations for photons coupled to a Rydberg superatom

Nina Stiesdal·Jan Kumlin·Kevin Kleinbeck·Philipp Lunt·Christoph Braun·Asaf Paris-Mandoki·Christoph Tresp·Hans Peter Büchler·Sebastian Hofferberth
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Abstract

We report on the experimental observation of non-trivial three-photon correlations imprinted onto initially uncorrelated photons through interaction with a single Rydberg superatom. Exploiting the Rydberg blockade mechanism, we turn a cold atomic cloud into a single effective emitter with collectively enhanced coupling to a focused photonic mode which gives rise to clear signatures in the connected part of the three-body correlation function of the out-going photons. We show that our results are in good agreement with a quantitative model for a single, strongly coupled Rydberg superatom. Furthermore, we present an idealized but exactly solvable model of a single two-level system coupled to a photonic mode, which allows for an interpretation of our experimental observations in terms of bound states and scattering states.

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Nina Stiesdal, Jan Kumlin, Kevin Kleinbeck, Philipp Lunt, Christoph Braun, Asaf Paris-Mandoki, Christoph Tresp, Hans Peter Büchler, Sebastian Hofferberth. 2018-05-31. Observation of three-body correlations for photons coupled to a Rydberg superatom. https://doi.org/10.1103/physrevlett.121.103601

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