Charge Exchange Dynamics in Cold Collisions of $^{40}$CaH$^+$ and $^{39}$K
Abstract
We report the observation of charge-exchange collisions between trapped calcium monohydride molecular ions (CaH) and ultracold potassium atoms (K) in a hybrid ion-atom trap. The measured charge-exchange rate coefficient is significantly suppressed relative to the Langevin rate constant for the system. We use quantum-chemical calculations to model the (CaH-K) system in the ground and excited electronic states and to identify possible charge-exchange mechanisms. Our calculations do not fully explain the measured rate, highlighting the need for a full-dimensional quantum treatment that includes vibrational motion and intermediate complex formation. Our work demonstrates that cold hybrid ion-atom platforms with molecular ions enable access to richer chemical complexity and collisional dynamics inaccessible in purely atomic systems.
Keywords
Cite
@article{arxiv.2602.09142,
title = {Charge Exchange Dynamics in Cold Collisions of $^{40}$CaH$^+$ and $^{39}$K},
author = {Swapnil Patel and Dibyendu Sardar and Jyothi Saraladevi and Michał Tomza and Kenneth R. Brown},
journal= {arXiv preprint arXiv:2602.09142},
year = {2026}
}