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arXiv · 1905.06846

Photo-induced two-body loss of ultracold molecules

Arthur Christianen·Martin W. Zwierlein·Gerrit C. Groenenboom·Tijs Karman
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Abstract

The lifetime of nonreactive ultracold bialkali gases was conjectured to be limited by sticky collisions amplifying three-body loss. We show that the sticking times were previously overestimated and do not support this hypothesis. We find that electronic excitation of NaK+NaK collision complexes by the trapping laser leads to the experimentally observed two-body loss. We calculate the excitation rate with a quasiclassical, statistical model employing ab initio potentials and transition dipole moments. Using longer laser wavelengths or repulsive box potentials may suppress the losses.

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Arthur Christianen, Martin W. Zwierlein, Gerrit C. Groenenboom, Tijs Karman. 2019-05-16. Photo-induced two-body loss of ultracold molecules. https://doi.org/10.1103/physrevlett.123.123402

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