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arXiv · 2002.00048

Observation of Collisions between Two Ultracold Ground-State CaF Molecules

Lawrence W. Cheuk·Loïc Anderegg·Yicheng Bao·Sean Burchesky·Scarlett Yu·Wolfgang Ketterle·Kang-Kuen Ni·John M. Doyle
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Abstract

We measure inelastic collisions between ultracold CaF molecules by combining two optical tweezers, each containing a single molecule. We observe collisions between $^2\Sigma$ CaF molecules in the absolute ground state $|X,v=0, N=0,F=0\rangle$, and in excited hyperfine and rotational states. In the absolute ground state, we find a two-body loss rate of $7(4) \times 10^{-11} \text{cm}^{3}/\text{s}$, which is below, but close to the predicted universal loss rate.

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Lawrence W. Cheuk, Loïc Anderegg, Yicheng Bao, Sean Burchesky, Scarlett Yu, Wolfgang Ketterle, Kang-Kuen Ni, John M. Doyle. 2020-01-31. Observation of Collisions between Two Ultracold Ground-State CaF Molecules. https://doi.org/10.1103/physrevlett.125.043401

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