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arXiv · 2506.01831

Non-adiabatically driven quantum interference effects in the ultracold K + KRb $\longrightarrow$ Rb + K$_{2}$ chemical reaction

H. da Silva Jr.·B. K. Kendrick·H. Li·S. Kotochigova·N. Balakrishnan
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Abstract

The K + KRb $\longrightarrow$ Rb + K$_{2}$ chemical reaction is the first ultracold atom-diatom chemical reaction for which experimental results have been reported for temperatures below 1 $\mu$K more than a decade ago. The reaction occurs through coupling with an excited electronic state that is accessible even in the ultracold limit. A previous quantum dynamics study, excluding non-adiabatic effects, has reported a rate coefficient that is about 35\% below the experimental value. Here, we report the first non-adiabatic quantum dynamics study of this reaction and obtain rate coefficients in better agreement with experiments. Our results show that short-range dynamics mediated by coupling with the excited electronic state introduces quantum interference effects that influence both the state-to-state rate coefficients and the overall reaction rates.

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H. da Silva Jr., B. K. Kendrick, H. Li, S. Kotochigova, N. Balakrishnan. 2025-06-02. Non-adiabatically driven quantum interference effects in the ultracold K + KRb $\longrightarrow$ Rb + K$_{2}$ chemical reaction. https://arxiv.org/abs/2506.01831

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