Confinement-induced stabilization of a resonantly interacting ultracold Bose-Fermi mixture

Ultra-cold mixtures have the potential to be excellent systems for exploring a wide range of phenomena such as phase separation, pair superfluidity, polaron formation, and fermion-mediated interactions. However, testing theoretical predictions for strongly interacting mixtures is challenging due to the three-body losses in these systems. We demonstrate experimentally that a resonantly interacting mixture of ultracold 87Rb and 87Sr gases exhibits a pronounced reduction of both heating and decay when confined to the quasi-2D regime by an optical lattice potential. The stabilization of the mixture results in lifetimes of several hundred milliseconds without observable heating and is attributed to a strong suppression of the detrimental effects of three-body collisions. The observed stabilization should also apply to other resonantly interacting mixtures and yields an excellent starting point for creating ultracold ground-state molecules and for exploring novel regimes in strongly interacting ultracold mixtures.