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arXiv · 1908.11839

Long rotational coherence times of molecules in a magnetic trap

L. Caldwell·H. J. Williams·N. J. Fitch·J. Aldegunde·Jeremy M. Hutson·B. E. Sauer·M. R. Tarbutt
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Abstract

Polar molecules in superpositions of rotational states exhibit long-range dipolar interactions, but maintaining their coherence in a trapped sample is a challenge. We present calculations that show many laser-coolable molecules have convenient rotational transitions that are exceptionally insensitive to magnetic fields. We verify this experimentally for CaF where we find a transition with sensitivity below 5 Hz G$^{-1}$ and use it to demonstrate a rotational coherence time of 6.4(8) ms in a magnetic trap. Simulations suggest it is feasible to extend this to more than 1 s using a smaller cloud in a biased magnetic trap.

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L. Caldwell, H. J. Williams, N. J. Fitch, J. Aldegunde, Jeremy M. Hutson, B. E. Sauer, M. R. Tarbutt. 2020-01-28. Long rotational coherence times of molecules in a magnetic trap. https://doi.org/10.1103/physrevlett.124.063001

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