Chaotic scattering and microwave loss suppression in the NaRb system

We report two recent results on atom-molecule and molecule-molecule collisions in the ^{23}Na^{87}Rb system. In the former case, we observe in total over 100 Feshbach resonances between ^{87}Rb atoms and ground-state ^{23}Na^{87}Rb molecules. A preliminary statistical analysis reveals that the chaotic distribution of these resonances. In the latter case, we use microwave dressing to suppress the loss induced by the complex formation and achieve a two-body loss rate coefficient of 9 * 10^{-13} cm^3s^{-1}. We also observe enhanced elastic collision rates as high as 2 * 10^{-9} cm^3s^{-1}. The large elastic to inelastic ratio should allow efficient evaporative cooling toward NaRb samples with higher phase space densities.