Rapid Cooling to Quantum Degeneracy in Dynamically Shaped Atom Traps

We report on a general method for the rapid production of quantum degenerate gases. Using $^{174}$Yb, we achieve an experimental cycle time as low as $(1.6\!-\!1.8)\,$s for the production of Bose-Einstein condensates (BECs) of $(0.5\!-\!1)\!\times\!10^5$ atoms. While laser cooling to $30\,\mu$K proceeds in a standard way, evaporative cooling is highly optimized by performing it in an optical trap that is dynamically shaped by utilizing the time-averaged potential of a single laser beam moving rapidly in one dimension. We also produce large ($>\!10^6$) atom number BECs and successfully model the evaporation dynamics over more than three orders of magnitude in phase space density. Our method provides a simple and general approach to solving the problem of long production times of quantum degenerate gases.