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Observation of Superfluid Flow in a Bose-Einstein Condensed Gas

R. Onofrio·C. Raman·J. M. Vogels·J. Abo-Shaeer·A. P. Chikkatur·W. Ketterle
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Abstract

We have studied the hydrodynamic flow in a Bose-Einstein condensate stirred by a macroscopic object, a blue detuned laser beam, using nondestructive {\em in situ} phase contrast imaging. A critical velocity for the onset of a pressure gradient has been observed, and shown to be density dependent. The technique has been compared to a calorimetric method used previously to measure the heating induced by the motion of the laser beam.

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R. Onofrio, C. Raman, J. M. Vogels, J. Abo-Shaeer, A. P. Chikkatur, W. Ketterle. 2000-06-07. Observation of Superfluid Flow in a Bose-Einstein Condensed Gas. https://doi.org/10.1103/physrevlett.85.2228

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