Thomas J. Greytak

With Kleppner began to study ultracold atomic hydrogen in the pursuit of Bose-Einstein condensation (BEC), which was accomplished in 1998. This effort led to discoveries in ultracold collisions and quantum reflection but the biggest impact was the invention and demonstration of evaporative cooling, along with Greytak's postdoc, Hess. Evaporative cooling of alkali atoms led to the observation of BEC in such systems in 1995, and all experimental realizations of BECs and degenerate Fermi gases use evaporative cooling as the final step. Thus their work triggered a whole new subfield of atomic and low temperature physics, the study of gaseous BEC.