${\mathrm{NaCs}}^{+}$ is theoretically assessed as a candidate platform for coherent optical control of ultracold molecular ions. Through high-level ab initio calculations with scalar-relativistic pseudopotentials, accurate potential energy curves are obtained for the Λ–S states, including Ω-resolved components under spin-orbit coupling. Agreement between the resulting spectroscopic constants and dissociation limits with available data is observed at the few-percent level. From the computed electronic states, $B^2{\mathrm{\Pi }}_{3/2}-X^2{\mathrm{\Sigma }}^{+}$ lifetimes of $25\text{–}31\mathrm{ns}$ are determined and Franck–Condon factors are extensively mapped. Specific $B^2{\mathrm{\Pi }}_{3/2}-X^2{\mathrm{\Sigma }}^{+}$ Raman pathways with favorable overlap products are identified, enabling efficient population transfer into $X^2{\mathrm{\Sigma }}^{+}$ ($v=0$, $J=0$). Combined with a realistic two-color photoassociative-ionization source in a Na–Cs magneto-optical trap overlap, a feasible route to preparing ultracold ${\mathrm{NaCs}}^{+}$ is outlined by our results.

Close

PrevNext

View figure in article

• Cold and ultracold molecules
• Cooling & trapping