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Sound Propagation in Elongated Bose-Einstein Condensed Clouds

G. M. Kavoulakis·C. J. Pethick
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Abstract

We consider propagation of sound pulses along the long axis of a Bose-Einstein condensed cloud in a very anisotropic trap. In the linear regime, we demonstrate that the square of the velocity of propagation is given by the square of the local sound velocity, $c^2=nU_0/m$, averaged over the cross section of the cloud. We also carry out calculations in the nonlinear regime, and determine how the speed of the pulse depends on its amplitude.

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G. M. Kavoulakis, C. J. Pethick. 1997-11-21. Sound Propagation in Elongated Bose-Einstein Condensed Clouds. https://doi.org/10.1103/physreva.58.1563

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