Observation of a shape resonance in cold-atom scattering by pulsed photoassociation

Abstract

We observe the time dependence of a cold-atom collision in a pulsed photoassociation experiment. For a g-wave shape resonance in the 85Rb+85Rb system we measure the time needed to build up the resonant state by tunneling through the centrifugal barrier. Combining this with time-independent 85Rb and 87Rb photoassociation we determine the resonance energy and find evidence for the decay of the shape resonance into inelastic channels. We also determine the 85Rb+ 85Rb and 87Rb+87Rb C6 coefficient and triplet scattering lengths without relying on ab initio calculations. © 1996 The American Physical Society.