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arXiv · 2101.04309

Dark-state sideband cooling in an atomic ensemble

Chang Huang·Shijie Chai·Shau-Yu Lan
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Abstract

We utilize the dark state in a Λ-type three-level system to cool an ensemble of 85Rb atoms in an optical lattice [Morigi et al., Phys. Rev. Lett. 85, 4458 (2000)]. The common suppression of the carrier transition of atoms with different vibrational frequencies allows them to reach a subrecoil temperature of 100 nK after being released from the optical lattice. A nearly zero vibrational quantum number is determined from the time-of-flight measurements and adiabatic expansion process. The features of sideband cooling are examined in various parameter spaces. Our results show that dark-state sideband cooling is a simple and compelling method for preparing a large ensemble of atoms into their vibrational ground state of a harmonic potential and can be generalized to different species of atoms and molecules for studying ultracold physics that demands recoil temperature and below.

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Chang Huang, Shijie Chai, Shau-Yu Lan. 2021-01-12. Dark-state sideband cooling in an atomic ensemble. https://doi.org/10.1103/physreva.103.013305

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