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Atom-molecule collisions in an optically trapped gas

Nassim Zahzam·Thibault Vogt·Marcel Mudrich·Daniel Comparat·Pierre Pillet
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Abstract

Cold inelastic collisions between confined cesium (Cs) atoms and Cs$\_2$ molecules are investigated inside a CO$\_2$ laser dipole trap. Inelastic atom-molecule collisions can be observed and measured with a rate coefficient of $\sim 2.5 \times 10^{-11} $cm$^3$ s$^{-1}$, mainly independent of the molecular ro-vibrational state populated. Lifetimes of purely atomic and molecular samples are essentially limited by rest gas collisions. The pure molecular trap lifetime ranges 0,3-1 s, four times smaller than the atomic one, as is also observed in a pure magnetic trap. We give an estimation of the inelastic molecule-molecule collision rate to be $\sim 10^{-11}$ cm$^{3}$ s$^{-1}$.

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Nassim Zahzam, Thibault Vogt, Marcel Mudrich, Daniel Comparat, Pierre Pillet. 2005-09-23. Atom-molecule collisions in an optically trapped gas. https://doi.org/10.1103/physrevlett.96.023202

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