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arXiv · 1511.09427

Optoelectrical cooling of polar molecules to sub-millikelvin temperatures

Alexander Prehn·Martin Ibrügger·Rosa Glöckner·Gerhard Rempe·Martin Zeppenfeld
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Abstract

We demonstrate direct cooling of gaseous formaldehyde (H2CO) to the microkelvin regime. Our approach, optoelectrical Sisyphus cooling, provides a simple dissipative cooling method applicable to electrically trapped dipolar molecules. By reducing the temperature by three orders of magnitude and increasing the phase-space density by a factor of ~$10^4$ we generate an ensemble of $3\cdot10^5$ molecules with a temperature of about 420μK, populating a single rotational state with more than 80% purity.

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Alexander Prehn, Martin Ibrügger, Rosa Glöckner, Gerhard Rempe, Martin Zeppenfeld. 2016-02-18. Optoelectrical cooling of polar molecules to sub-millikelvin temperatures. https://doi.org/10.1103/physrevlett.116.063005

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