arXiv:2003.07850 · Physical Review Letters

Forming a Single Molecule by Magnetoassociation in an Optical Tweezer

Jessie T. Zhang, Yichao Yu, William B. Cairncross, Kenneth Wang, Lewis R. B. Picard, Jonathan D. Hood, Yen-Wei Lin, Jeremy M. Hutson, Kang-Kuen Ni

Published Jun 25, 2020• 71 citations

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Abstract

We demonstrate the formation of a single NaCs molecule in an optical tweezer by magnetoassociation through an s-wave Feshbach resonance at 864.11(5) G. Starting from single atoms cooled to their motional ground states, we achieve conversion efficiencies of 47(1)%, and measure a molecular lifetime of 4.7(7) ms. By construction, the single molecules are predominantly [77(5)%] in the center-of-mass motional ground state of the tweezer. Furthermore, we produce a single p-wave molecule near 807 G by first preparing one of the atoms with one quantum of motional excitation. Our creation of a single weakly bound molecule in a designated internal state in the motional ground state of an optical tweezer is a crucial step towards coherent control of single molecules in optical tweezer arrays.

DOI: 10.1103/physrevlett.124.253401

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