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Chinese Physics B

High efficient Raman sideband cooling and strong three-body recombination of atoms

Yuqing 玉清 Li 李, Zhennan 震南 Liu 刘, Yunfei 云飞 Wang 王, Jizhou 寄洲 Wu 武, Wenliang 文良 Liu 刘, Yongming 永明 Fu 付, Peng 鹏 Li 李, Jie Ma, Liantuan Xiao, Suotang 锁堂 Jia 贾

Published Aug 1, 2023• 2 citations
Publisher

Abstract

We report a highly efficient three-dimensional degenerated Raman sideband cooling (3D dRSC) that enhances the loading of a magnetically levitated optical dipole trap, and observe the strong atom loss due to the three-body recombination. The 3D dRSC is implemented to obtain 5 × 107 Cs atoms with the temperature of ∼ 480 nK. The cold temperature enables 1.8 × 107 atoms loaded into a crossed dipole trap with an optimized excessive levitation magnetic gradient. Compared to the loading of atoms from a bare magneto-optical trap or the gray-molasses cooling, there is a significant increase in the number of atoms loaded into the optical dipole trap. We derive for the three-body recombination coefficient of L 3 = 7.73 × 10−25 cm6/s by analyzing the strong atom loss at a large scattering length of 1418 Bohr radius, and discover the transition from the strong three-body loss to the dominant one-body loss. Our result indicates that the lifetime of atoms in the optical dipole trap is finally decided by the one-body loss after the initial strong three-body loss.

DOI
10.1088/1674-1056/acec42

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