Suppression of Molecular Decay in Ultracold Gases without Fermi Statistics

We study inelastic processes for ultracold three-body systems in which only one interaction is resonant. We show that at ultracold temperatures three-body recombination in such systems leads mainly to the formation of weakly bound molecules. In addition, and perhaps more importantly, we have found that the decay rates for weakly bound molecules due to collisions with other atoms can be suppressed not only without fermionic statistics but also when bosonic statistics applies. These results indicate that recombination in three-component atomic gases can be used as an efficient mechanism for molecular formation, allowing the achievement of high molecular densities.

Figure 1

(a) Vibrational relaxation rate from weakly bound $X{Y}^{*}$ molecules and (b) three-body recombination rates into weakly ($K_3^w$) and deeply ($K_3^d$) bound molecules.