Consequence of superfluidity on the expansion of a rotating Bose-Einstein condensate.
We propose an easily detectable signature of superfluidity in rotating, vortex-free gaseous Bose-Einstein condensates. We have studied the time evolution of the expansion of such a condensate after it is released from the confining trap. We find that if such a condensate is not initially rotating, then at some moment it will instantaneously achieve a circular cross section. If the condensate is initially rotating its irrotational flow and the conservation of angular momentum prevent the released condensate from attaining a circular cross section, since the instantaneous moment of inertia is then proportional to the asymmetry of this cross section.
Edwards
Mark
M
Department of Physics, Georgia Southern University, Statesboro, Georgia 30460-803, USA.
Clark
Charles W
CW
Pedri
P
P
Pitaevskii
L
L
Stringari
S
S