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arXiv · 2607.08421

Fourier imaging of collective spontaneous emission modes in superradiant cold atomic clouds

Adrien Gavalda·Guillaume Tremblier·Martin Poitrinal·Sara Pancaldi·Antoine Browaeys·Igor Ferrier-Barbut
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Abstract

We measure the spatial pattern associated with the superradiant emission from a cloud of cold 87Rb atoms using Fourier imaging. We observe a highly directional, ring-shaped emission structure, which corresponds to a single collective jump operator associated to the most superradiant mode of the ensemble. Using spatial filtering, we isolate this channel and find the typical superradiant burst with superlinear scaling of the intensity with atom number. We compare our results to two models that describe the competition between the various decay channels, finding good agreement. Our work shows that the collective jump operators introduced by Carmichael et al. [Optics Communications 179, 417 (2000)] can be measured and manipulated.

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Adrien Gavalda, Guillaume Tremblier, Martin Poitrinal, Sara Pancaldi, Antoine Browaeys, Igor Ferrier-Barbut. 2026-07-09. Fourier imaging of collective spontaneous emission modes in superradiant cold atomic clouds. https://arxiv.org/abs/2607.08421

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