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Condensation of phonons in an ultracold Bose gas

Yu. Kagan·L. A. Manakova
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Abstract

We consider the generation of longitudinal phonons in an elongated Bose-condensed gas at zero temperature due to parametric resonance as a result of the modulation of the transverse trap frequency. The nonlinear temporal evolution with account of the phonon-phonon interaction leads self-consistently to the formation of the stationary state with the macroscopic occupation of a single phonon quantum state.

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Yu. Kagan, L. A. Manakova. 2006-09-07. Condensation of phonons in an ultracold Bose gas. https://doi.org/10.1016/j.physleta.2006.09.106

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