Cooling dynamics of an alkali-lanthanide mixture

We report co-trapping and sympathetic cooling of an erbium-lithium mixture. We first load atoms into magneto-optical traps, followed by sub-Doppler cooling in the case of lithium, then sequentially load each species into a large-volume optical dipole trap. Due to its lower polarizability, the erbium gas serves as a coolant for lithium, while the large mass ratio necessitates a high elastic scattering rate. Numerous Feshbach resonances provide control of interspecies thermalization.