Transition Strength Measurements to Guide Magic Wavelength Selection in Optically Trapped Molecules

Optical trapping of molecules with long coherence times is crucial for many protocols in quantuminformation and metrology. However, the factors that limit the lifetimes of the trapped molecules remainelusive and require improved understanding of the underlying molecular structure. Here we show thatmeasurements of vibronic line strengths in weakly and deeply bound88Sr2molecules, combined withab initiocalculations, allow for unambiguous identification of vibrational quantum numbers. This, in turn,enables the construction of refined excited potential energy curves, informing the selection of magicwavelengths that facilitate long vibrational coherence. We demonstrate Rabi oscillations between far-separated vibrational states that persist for nearly 100 ms