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Condensation of phonons in an ultracold Bose gas

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 نشر من قبل Lyubov' Manakova A.
 تاريخ النشر 2006
  مجال البحث فيزياء
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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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