Interaction-driven dynamics of K40-Rb87 fermion-boson gas mixtures in the large-particle-number limit

We have studied effects of interspecies attraction in a Fermi-Bose mixture over a large regime of particle numbers in the K40-Rb87 system. We report on the observation of a mean-field driven collapse at critical particle numbers of 1.2×106 Rb87 atoms in the condensate and 7.5×105 K40 atoms consistent with mean-field theory for a scattering length of aFB=-284a0. For large overcritical particle numbers, we see evidence for revivals of the collapse. Part of our detailed study of the decay dynamics and mechanisms is a measurement of the (Rb87-Rb87-K40) three-body loss coefficient K3=(2.8±1.1)×10-28cm6/s, which is an important parameter for dynamical studies of the system.