A pumped atom laser

The atom laser, a bright, coherent matter wave derived from a Bose-Einstein condensate, holds great promise for precision measurement and for fundamental tests of quantum mechanics. But despite significant experimental efforts, no method has been demonstrated to enable continuous and irreversible replenishment of a trapped Bose-Einstein condensate while simultaneously producing a free, coherent atom beam. Here, we report an experiment that uses two spatially separated Bose-Einstein condensates of rubidium in different internal hyperfine states, and show that while continuously output-coupling an atom laser beam from one Bose-Einstein condensate, we can simultaneously and irreversibly pump new atoms from a physically separate cloud into the trapped condensate that forms the lasing mode.