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Observation of Persistent Flow of a Bose-Einstein Condensate in a Toroidal Trap



Changhyun Ryu, Mikkel Andersen, Pierre Clade, Vasant Natarajan, Kristian Helmerson, William D. Phillips


We have observed the persistent flow of Bose-condensed atoms in a toroidal trap. The flow persists without decay for up to 10 s, limited only by experimental factors such as drift and trap lifetime. The quantized rotation was initiated by transferring one unit, h, of the orbital angular momentum from Laguerre-Gaussian photons to the atoms. Stable flow was only possible when the trap was multiply-connected, and was observed with a BEC fraction as small as 15%. We also created flow with two units of angular momentum, and observed its splitting into two singly-charged vortices when the trap geometry was changed from multiply- to simply-connected.
Physical Review Letters


BEC, persistent flow, superfluidity, toroidal, vortex pinning


Ryu, C. , Andersen, M. , Clade, P. , Natarajan, V. , Helmerson, K. and Phillips, W. (2008), Observation of Persistent Flow of a Bose-Einstein Condensate in a Toroidal Trap, Physical Review Letters (Accessed February 28, 2024)
Created October 16, 2008