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arXiv · 2101.07544

Fast and efficient preparation of 1D chains and dense cold atomic clouds

Abstract

We report the efficient and fast ($\sim 2\mathrm{Hz}$) preparation of randomly loaded 1D chains of individual $^{87}$Rb atoms and of dense atomic clouds trapped in optical tweezers using a new experimental platform. This platform is designed for the study of both structured and disordered atomic systems in free space. It is composed of two high-resolution optical systems perpendicular to each other, enhancing observation and manipulation capabilities. The setup includes a dynamically controllable telescope, which we use to vary the tweezer beam waist. A D1 $Λ$-enhanced gray molasses enhances the loading of the traps from a magneto-optical trap. Using these tools, we prepare chains of up to $\sim 100$ atoms separated by $\sim 1 \mathrm{μm}$ by retro-reflecting the tweezer light, hence producing a 1D optical lattice with strong transverse confinement. Dense atomic clouds with peak densities up to $n_0 = 10^{15}\:\mathrm{at}/\mathrm{cm}^3$ are obtained by compression of an initial cloud. This high density results into interatomic distances smaller than $λ/(2π)$ for the D2 optical transitions, making it ideal to study light-induced interactions in dense samples.

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Antoine Glicenstein, Giovanni Ferioli, Ludovic Brossard, Yvan R. P. Sortais, Daniel Barredo, Florence Nogrette, Igor Ferrier-Barbut, Antoine Browaeys. 2021-01-19. Fast and efficient preparation of 1D chains and dense cold atomic clouds. https://doi.org/10.1103/physreva.103.043301

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