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arXiv · 1511.07360

Rotational cooling of trapped polyatomic molecules

Rosa Glöckner·Alexander Prehn·Barbara G. U. Englert·Gerhard Rempe·Martin Zeppenfeld
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Abstract

Controlling the internal degrees of freedom is a key challenge for applications of cold and ultracold molecules. Here, we demonstrate rotational-state cooling of trapped methyl fluoride molecules (CH3F) by optically pumping the population of 16 M-sublevels in the rotational states J=3,4,5, and 6 into a single level. By combining rotational-state cooling with motional cooling, we increase the relative number of molecules in the state J=4, K=3, M=4 from a few percent to over 70%, thereby generating a translationally cold (~30mK) and nearly pure state ensemble of about 10^6 molecules. Our scheme is extendable to larger sets of initial states, other final states and a variety of molecule species, thus paving the way for internal-state control of ever larger molecules.

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Rosa Glöckner, Alexander Prehn, Barbara G. U. Englert, Gerhard Rempe, Martin Zeppenfeld. 2015-11-23. Rotational cooling of trapped polyatomic molecules. https://doi.org/10.1103/physrevlett.115.233001

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