Coherent Control of Penning and Associative Ionization: Insights from Symmetries

Coherent control of reactive atomic and molecular collision processes remains elusive experimentally due to quantum interference-based requirements. Here, with insights from symmetry conditions, a viable method for controlling Penning and associative ionization in atomic collisions is proposed. Computational applications to ${\mathrm{He}}^{*}({}^{3}S)\text{−}\mathrm{Li}({}^{2}S)$ and ${\mathrm{Ne}}^{*}({}^3{P}_2)\text{−}\mathrm{Ar}({}^1{S}_0)$ show extensive control over the ionization processes under experimentally feasible conditions.

Figure 1

Cross sections for AI (upper panel), PI (middle panel), and the ratio of the two (lower panel) in the ${\mathrm{Ne}}^{*}\text{−}\mathrm{Ar}$ system for the state (22), as a function of the control parameters $\eta$ and $\xi$. The collision energy is 50 mK, and the cross sections are given in atomic units.