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arXiv · 1803.04571

Laser Cooling of Optically Trapped Molecules

Loïc Anderegg·Benjamin L. Augenbraun·Yicheng Bao·Sean Burchesky·Lawrence W. Cheuk·Wolfgang Ketterle·John M. Doyle
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Abstract

Calcium monofluoride (CaF) molecules are loaded into an optical dipole trap (ODT) and subsequently laser cooled within the trap. Starting with magneto-optical trapping, we sub-Doppler cool CaF and then load $150(30)$ CaF molecules into an ODT. Enhanced loading by a factor of five is obtained when sub-Doppler cooling light and trapping light are on simultaneously. For trapped molecules, we directly observe efficient sub-Doppler cooling to a temperature of $60(5)$ $\mu\text{K}$. The trapped molecular density of $8(2)\times10^7$ cm$^{-3}$ is an order of magnitude greater than in the initial sub-Doppler cooled sample. The trap lifetime of 750(40) ms is dominated by background gas collisions.

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Loïc Anderegg, Benjamin L. Augenbraun, Yicheng Bao, Sean Burchesky, Lawrence W. Cheuk, Wolfgang Ketterle, John M. Doyle. 2018-03-12. Laser Cooling of Optically Trapped Molecules. https://doi.org/10.1038/s41567-018-0191-z

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