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Superradiance from BEC vortices: a numerical study

F. Federici·C. Cherubini·S. Succi·M. P. Tosi
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Abstract

The scattering of sound wave perturbations from vortex excitations of Bose-Einstein condensates(BEC) is investigated by numerical integration of the associated Klein-Gordon equation. It is found that, at sufficiently high angular speeds, sound wave-packets can extract a sizeable fraction of the vortex energy through a mechanism of superradiant scattering. It is conjectured that this superradiant regime may be detectable in BEC experiments.

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F. Federici, C. Cherubini, S. Succi, M. P. Tosi. 2005-03-21. Superradiance from BEC vortices: a numerical study. https://doi.org/10.1103/physreva.73.033604

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