Precision Science with Ultracold Strontium Dimers

Molecules offer a new paradigm for precision measurements. Homonuclear alkaline-earth dimers are an attractive species owing to their amenability to ab initio quantum chemistry modeling, the natural existence of dipole-forbidden vibrational transitions, molecular subradiance, and narrow triplet electronic states. We demonstrate how light shifts induced by the optical lattice trap on a narrow vibrational Raman transition can be used to accurately determine molecular polarizability ratios and transition strengths. We have mapped out all 63 vibrational states with J=0 and J=2 belonging to the X¹Σ_g⁺ ground potential in ⁸⁸Sr₂, and we compare the binding energies to ab initio calculations. We also report the all-optical creation of strontium dimers in the absolute rovibrational ground state via a singlet dominant channel in (1)0_u⁺ using STIRAP and discuss prospects for optical trapping in a mid-IR magic lattice to maximize the coherence time of the molecular clock states.