We have investigated rovibronic levels of the strongly mixed $b{}^3\mathrm{\Pi }_1–c{}^3\mathrm{\Sigma }_1^{+}–B{}^1\mathrm{\Pi }_1$ states [the 2(1), 3(1), and 4(1) states in Hund's case (c) notation] of ${}^{85}\mathrm{Rb}{}^{133}\mathrm{Cs}$ in the energy range of 13 950–14 200 ${\mathrm{cm}}^{-1}$ using short-range photoassociation (PA). For selected PA states, vibrational and rotational branching in the $X{}^1{\mathrm{\Sigma }}^{+}$ state have been investigated using resonance-enhanced multiphoton ionization and depletion spectroscopy. Efficient production of ${}^{85}\mathrm{Rb}{}^{133}\mathrm{Cs}$ molecules in the rovibronic-ground-state $X{}^1{\mathrm{\Sigma }}^{+}$ ($v=0, J=0$), at up to $\sim 1\times {10}^4$ molecules/s, has been achieved.

• Received 6 February 2018

DOI:https://doi.org/10.1103/PhysRevA.98.043423