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Observation of the scissors mode and superfluidity of a trapped Bose-Einstein condensed gas

O. M. Marago'·S. A. Hopkins·J. Arlt·E. Hodby·G. Hechenblaikner·C. J. Foot
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Abstract

We report the observation of the scissors mode of a Bose-Einstein condensed gas of 87^Rb atoms in a magnetic trap, which gives direct evidence of superfluidity in this system. The scissors mode of oscillation is excited by a sudden rotation of the anisotropic trapping potential. For a gas above T_c (normal fluid) we detect the occurrence of oscillations at two frequencies, with the lower frequency corresponding to the rigid body value of the moment of inertia. Well below T_c the condensate oscillates at a single frequency, without damping, as expected for a superfluid.

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O. M. Marago', S. A. Hopkins, J. Arlt, E. Hodby, G. Hechenblaikner, C. J. Foot. 1999-11-12. Observation of the scissors mode and superfluidity of a trapped Bose-Einstein condensed gas. https://doi.org/10.1103/physrevlett.84.2056

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