Nathan Gilfoy

We measure the inelastic collision rates of ultracold, vibrationally excited RbCs molecules with Rb and Cs atoms. In order to do this we have demonstrated simultaneous optical trapping of T = 250 μK RbCs molecules and their constituent atoms. Electronic ground state, vibrationally excited RbCs molecules are created via photoassociation from laser-cooled samples of Rb and Cs atoms. A sample of consisting of molecules, atoms, or a combination of the two can be confined in a far red detuned optical lattice. Measurements of the trap lifetimes of the molecules in the lattice show background-gas limited collision rates for the molecules. Co-trapping atoms with the molecules results in strong inelastic collisions in the sample. We used state-sensitive detection to measure the molecular scattering rate with the two species of atoms over an order of magnitude in molecular binding energies. We find that there is no dependence of the molecule-atom cross-section on molecular vibrational quantum number.