Breaking down superfluidity

“One of the most exciting areas of research in the last few years has been the realization of the BEC-BCS crossover,” Wolfgang Ketterle tells PhsyOrg.com. Ketterle and a team of scientists at the MIT-Harvard Center for Ultracold Atoms have completed the first study of critical velocities in this crossover region where magnetic tuning of the interactions is possible by a Feshbach resonance.