Production of a dual-species Bose-Einstein condensate of Rb and Cs atoms

We report the simultaneous production of Bose-Einstein condensates (BECs) of Rb-87 and Cs-133 atoms in separate optical traps. The two samples are mixed during laser cooling and loading but are separated by 400 mu m for the final stage of evaporative cooling. This is done to avoid considerable interspecies three-body recombination, which causes heating and evaporative loss. We characterize the BEC production process, discuss limitations, and outline the use of the dual-species BEC in future experiments to produce rovibronic ground state molecules, including a scheme facilitated by the superfluid-to-Mott-insulator (SF-MI) phase transition.