Towards studying interactions between trapped CaH⁺ions and K atoms

The complex internal structure of molecular ions poses challenges with employing direct laser cooling [1]. An alternative and more general approach is to sympathetically cool the external and internal degrees of freedom of the molecular ions using laser-cooled atomic ions and neutral atoms, respectively [2]. Our hybrid ion-atom trap is ideally suited for this method of ground-state cooling of a molecular ion [3], and our goal is to demonstrate this by sympathetically cooling calcium mono-hydride ions (CaH⁺) using co-trapped calcium (⁴⁰Ca⁺) ions and potassium (³⁹K) atoms. Moreover, the ability to simultaneously trap the three species, ⁴⁰Ca⁺, ³⁹K, and CaH⁺, allows for the study of various possible chemical reactions. Knowledge of and control over these reactions is paramount for our goal of cooling CaH⁺. We have already investigated the charge exchange between Ca⁺ and K and established the ability to quench the reaction rate [4]. In this talk, we expand on this work and present our progress towards studying the interactions between CaH⁺ ions and K atoms.

 

References:

[1] Nguyen, Jason HV, et al., New Journal of Physics 13.6 (2011): 063023

[2] Hudson, Eric R., EPJ Techniques and Instrumentation 3 (2016): 1-21

[3] Jyothi, S., et al., Review of Scientific Instruments 90.10 (2019): 103201

[4] Li, Hui, et al., Physical Chemistry Chemical Physics 22.19 (2020): 10870-10881