A dense gas of laser-cooled atoms for hybrid atom–ion trapping


We describe the realization of a dark spontaneous-force trap of rubidium atoms. The atoms are loaded from a beam provided by a two-dimensional magneto-optical trap yielding a capture efficiency of 75%. The dense and cold atomic sample is characterized by saturated absorption imaging. Up to \(10^9\) atoms are captured with a loading rate of \(3\times 10^9\) atoms/s into a cloud at a temperature of 250 \(\mu\)K with the density exceeding \(10^{11}\) atoms/cm\(^3\). Under steady-state conditions, more than 90% of the atoms can be prepared into the absolute atomic ground state, which provides favorable conditions for the investigation of sympathetic cooling of ions in a hybrid atom–ion trap.

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This work is supported in part by the Heidelberg Center for Quantum Dynamics and the BMBF under contract number 05P12VHFA6. B.H. acknowledges support by HGSHire.

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Correspondence to Matthias Weidemüller.

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This article is part of the topical collection “Enlightening the World with the Laser” - Honoring T. W. Hänsch guest edited by Tilman Esslinger, Nathalie Picqué, and Thomas Udem.

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Höltkemeier, B., Glässel, J., López-Carrera, H. et al. A dense gas of laser-cooled atoms for hybrid atom–ion trapping. Appl. Phys. B 123, 51 (2017). https://doi.org/10.1007/s00340-016-6624-4

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  • Probe Beam
  • Dark Spot
  • Atom Beam
  • Atom Cloud
  • Absorption Imaging