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arXiv · 2607.28873

Collimation of dense atomic beams by Swept Velocity Shelving

Francesca Famà·Benedikt Heizenreder·Ananya Sitaram·Camila Beli·Robert J. C. Spreeuw·Stefan A. Schäffer·Florian Schreck
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Abstract

Engineering continuous, high-flux, and collimated atomic beams is a useful resource for metrology and material deposition. Developments in this area have been essential for the evolution of cold-atom based quantum experiments, yet the ubiquitous balanced-force methods such as transverse molasses cooling degrade at high atomic flux due to absorption-induced force imbalance. We introduce a collimation scheme that combines the use of a broadband transition for velocity shifting with a narrowband transition for velocity selection, enabling velocity-selective beam collimation without relying on balanced-power counter-propagating beams. Collimated atoms are shelved in a long-lived internal state, reducing the total light scattering and providing a state-heralded collimated beam. Simulations using strontium as a model system show a highly effective collimation process that does not suffer from absorption-induced force-imbalance and experimental results agree well with these predictions.

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Francesca Famà, Benedikt Heizenreder, Ananya Sitaram, Camila Beli, Robert J. C. Spreeuw, Stefan A. Schäffer, Florian Schreck. 2026-07-30. Collimation of dense atomic beams by Swept Velocity Shelving. https://arxiv.org/abs/2607.28873

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