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arXiv · 1709.07419

Long-lived complexes and signatures of chaos in ultracold K2+Rb collisions

J. F. E. Croft·N. Balakrishnan·B. K. Kendrick
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Abstract

Lifetimes of complexes formed during ultracold collisions are of current experimental interest as a possible cause of trap loss in ultracold gases of alkali-dimers. Microsecond lifetimes for complexes formed during ultracold elastic collisions of K2 with Rb are reported, from numerically-exact quantum-scattering calculations. The reported lifetimes are compared with those calculated using a simple density-of-states approach, which are shown to be reasonable. Long-lived complexes correspond to narrow scattering resonances which we examine for the statistical signatures of quantum chaos, finding that the positions and widths of the resonances follow the Wigner-Dyson and Porter-Thomas distributions respectively.

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J. F. E. Croft, N. Balakrishnan, B. K. Kendrick. 2017-09-21. Long-lived complexes and signatures of chaos in ultracold K2+Rb collisions. https://doi.org/10.1103/physreva.96.062707

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