Free-bound excitation and predissociation of ytterbium dimers near theS01−P11atomic transition

Abstract

A continuous excitation band of a free-bound photoassociation transition of ytterbium atoms is observed as a red wing of the $^{1}S_{0}\text{\ensuremath{-}}^{1}P_{1}$ atomic line at 399 nm for a hot thermal vapor. The excitation to the ${0}_{u}^{+}$ molecular state is observed by monitoring fluorescence from the $^{3}P_{1}$ state atoms, which allows us to detect the production of ${\mathrm{Yb}}_{2}$ molecules with high sensitivity. The photoassociation is characterized in comparison with transitions to atomic Rydberg states. The time profile of the fluorescence signal suggests that the ${0}_{u}^{+}$ molecular state predissociates with states correlating to the $^{1}S_{0}+^{3}D_{2}$ atomic states.