Driving Bose-Einstein-Condensate Vorticity With a Rotating Normal Cloud

Published

November 1, 2001

Author(s)

P C. Haljan, Ian R. Coddington, P Engels, Eric A. Cornell

Abstract

We have developed an evaporative cooling technique that accelerates the circulation of an ultra-cold ⁸⁷Rb gas, confined in a static harmonicpotential. As a normal gas is evaporatively spun up and cooled below quantum degeneracy, it is found to nucleate vorticity in a Bose-Einsteincondensate. Measurements of the condensate's aspect ratio and surface-wave excitations are consistent with effective rigid-body rotation.Rotation rates of up to 94% of the centrifugal limit are inferred. A threshold in the normal cloud's rotation is observed for the intrinsic nucleation of the first vortex. The threshold value lies below the prediction for a nucleation mechanism involving the excitation of surface waves of the ground-state condensate.

Citation

Physical Review Letters

Volume

87

Issue

No. 21

Pub Type

Journals

Keywords

Bose-Einstein condensation, superfluidity

Citation

Haljan, P. , Coddington, I. , Engels, P. and Cornell, E. (2001), Driving Bose-Einstein-Condensate Vorticity With a Rotating Normal Cloud, Physical Review Letters (Accessed May 4, 2024)