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arXiv · 2407.14824

Ultracold charged atom-dimer collisions: state-selective charge exchange and three-body recombination

Amrendra Pandey·Romain Vexiau·Luis Gustavo Marcassa·Olivier Dulieu·Nadia Bouloufa-Maafa
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Abstract

Based on an accurate determination of the potential energy surfaces of Rb$_3^+$ correlated to its first asymptotic limit Rb$^+$$+$Rb($5s$)$+$Rb($5s$), we identify the presence of intersections of a pair of singlet and triplet surfaces over all interparticle distances, leading to Jahn-Teller couplings. We elaborate scenarios for charge exchange between ultracold charged atom-dimer complex (Rb$+$Rb$_2^+$ or Rb$^+$$+$Rb$_2$), predicting a strong selectivity on the preparation of the initial state of the dimer. We also demonstrate that the JT couplings must drive the three-body recombination (TBR) of Rb$^+$, Rb, and Rb at ultracold energies. Using the current analysis, we provide a consistent picture of the TBR experiments performed in ion-atom hybrid Rb samples \cite{dieterle2020inelastic,harter2012single}. We also demonstrate the presence of JT coupling as a general phenomenon in the singly-charged homonuclear alkali triatomic systems.

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Amrendra Pandey, Romain Vexiau, Luis Gustavo Marcassa, Olivier Dulieu, Nadia Bouloufa-Maafa. 2024-07-20. Ultracold charged atom-dimer collisions: state-selective charge exchange and three-body recombination. https://arxiv.org/abs/2407.14824

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