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arXiv · 0911.4906

Two-stream instability in quasi-one-dimensional Bose-Einstein condensates

H. Terças·J. T. Mendonça·G. R. M. Robb
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Abstract

We apply a kinetic model to predict the existence of an instability mechanism in elongated Bose-Einstein condensates. Our kinetic description, based on the Wigner formalism, is employed to highlight the existence of unstable Bogoliubov waves that may be excited in the counterpropagation configuration. We identify a dimensionless parameter, the Mach number at T = 0, that tunes different regimes of stability. We also estimate the magnitude of the main parameters at which two-stream instability is expected to be observed under typical experimental conditions.

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H. Terças, J. T. Mendonça, G. R. M. Robb. 2009-11-25. Two-stream instability in quasi-one-dimensional Bose-Einstein condensates. https://doi.org/10.1103/physreva.79.065601

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