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arXiv · 2608.10998

Non-resonant laser-driven narrowing of particle velocity distributions

Ashwini Vaishnav·Matthias Rupp·Olivier De Castro·Mikhail N. Shneider·Alexandros Gerakis
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Abstract

Stark acceleration and deceleration based techniques for generating particle ensembles with low velocity spread are useful in many experimental applications. For a given velocity distribution of a particle ensemble, these techniques accelerate or decelerate a small subset of the total population, with a low velocity uncertainty. However, narrowing the original velocity distribution by accelerating or decelerating the ensemble particles near the mean velocity is fundamentally limited and not yet explored. We present a numerical study of particle dynamics using neutral cesium atoms as an example. We investigate different interaction regimes, identify key limitations, and propose an interaction regime in which optical Stark deceleration can be used to narrow the velocity distribution of a propagating ensemble about its mean velocity. These findings have potential implications for optical manipulation and control, controlled collisions, and matter interferometry.

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Ashwini Vaishnav, Matthias Rupp, Olivier De Castro, Mikhail N. Shneider, Alexandros Gerakis. 2026-08-11. Non-resonant laser-driven narrowing of particle velocity distributions. https://arxiv.org/abs/2608.10998

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