Persistent flow in a Bose Einstein condensate

Changhyun Ryu , Pierre Cladé, Mikkel Andersen, Anand Ramanathan, Vasant Natarajan, Kristian Helmerson, and William D. Phillips

We will describe experiments on the study of quantized flow of Bose-condensed atoms in a multiply-connected trap. This torus-shaped trap is formed by the combination of an elliptically shaped, magnetic trap with a blue detuned laser beam to exclude atoms from the center of the magnetic trap. The rotation was initiated by transferring the orbital angular momentum from Laguerre-Gaussian photons to the atoms. We have observed that the rotational flow of atoms persists for several seconds, even when the condensate fraction is less than 10%. We interpret this as the first evidence of persistent current in a superfluid Bose gas.

Category:  Physics

Guest researcher involved:

Name:                         Pierre Cladé

Mentor's name:            Kristian Helmerson

Division:                       Atomic Physics Division (842)

Laboratory:                  Laser Cooling and Trapping Group

Address:                      Rm. B237, Bldg. 216, Stop 8424

Telephone #:                (301) 975-5231

FAX #:                        301-975-8272

email:                           pierre.clade@nist.gov

            Non Sigma Xi member

Name:                         Changhyun Ryu

Mentor's name:            Kristian Helmerson

Division:                       Atomic Physics Division (842)

Laboratory:                  Laser Cooling and Trapping Group

Address:                      Bldg. 216, Stop 8424

Telephone #:                (301) 975-6583

FAX #:                        301-975-8272

email:                           changhyun.ryu@nist.gov

            Non Sigma Xi member