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arXiv:2205.11381 · Physical Review A

Vibronic branching ratios for nearly closed rapid photon cycling of SrOH

Zack Lasner, Annika Lunstad, Chaoqun Zhang, Lan Cheng, John M. Doyle

Published Aug 3, 2022• 27 citations
arXivHTMLPDF

Abstract

The vibrational branching ratios of SrOH for radiative decay to the ground electronic state, $X{\phantom{\rule{0.16em}{0ex}}}^{2}{\mathrm{\ensuremath{\Sigma}}}^{+}$, from the first two electronically excited states, $A{\phantom{\rule{0.16em}{0ex}}}^{2}\mathrm{\ensuremath{\Pi}}$ and $B{\phantom{\rule{0.16em}{0ex}}}^{2}{\mathrm{\ensuremath{\Sigma}}}^{+}$, are determined experimentally at the $\ensuremath{\sim}{10}^{\ensuremath{-}5}$ level. The observed small branching ratios enable the design of a full, practical laser-cooling scheme, including magnetooptical trapping and sub-Doppler laser cooling, with $>{10}^{4}$ photon scatters per molecule. Ab initio calculations sensitive to weak vibronic transitions are performed to facilitate the experimental measurement and analysis, and show good agreement with the experiment.

DOI
10.1103/physreva.106.l020801

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