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arXiv · 1311.6297

Photoassociation of ultracold LiRb* molecules: observation of high efficiency and unitarity-limited rate saturation

Sourav Dutta·John Lorenz·Adeel Altaf·D. S. Elliott·Yong P. Chen
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Abstract

We report the production of ultracold heteronuclear 7Li85Rb molecules in excited electronic states by photoassociation (PA) of ultracold 7Li and 85Rb atoms. PA is performed in a dual-species 7Li-85Rb magneto-optical trap (MOT) and the PA resonances are detected using trap loss spectroscopy. We identify several strong PA resonances below the Li (2s 2S1/2) + Rb (5p 2P3/2) asymptote and experimentally determine the long range C6 dispersion coefficients. We find a molecule formation rate (P_LiRb) of 3.5x10^7 s^-1 and a PA rate coefficient (K_PA) of 1.3x10^-10 cm^3/s, the highest among heteronuclear bi-alkali molecules. At large PA laser intensity, we observe the saturation of the PA rate coefficient (K_PA) close to the theoretical value at the unitarity limit.

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Sourav Dutta, John Lorenz, Adeel Altaf, D. S. Elliott, Yong P. Chen. 2014-05-05. Photoassociation of ultracold LiRb* molecules: observation of high efficiency and unitarity-limited rate saturation. https://doi.org/10.1103/physreva.89.020702

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