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تسجيل مستخدم جديدFast and efficient preparation of 1D chains and dense cold atomic clouds
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We report the efficient and fast ($sim 2mathrm{Hz}$) 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 $Lambda$-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 $sim 1 mathrm{mu m}$ 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 $lambda/(2pi)$ for the D2 optical transitions, making it ideal to study light-induced interactions in dense samples.
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