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Depletion of a Bose-Einstein condensate by laser-iduced dipole-dipole interactions

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 نشر من قبل Igor E. Mazets
 تاريخ النشر 2003
  مجال البحث فيزياء
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We study a gaseous Bose-Einstein condensate with laser-induced dipole-dipole interactions using the Hartree-Fock-Bogoliubov theory within the Popov approximation. The dipolar interactions introduce long-range atom-atom correlations, which manifest themselves as increased depletion at momenta similar to that of the laser wavelength, as well as a roton dip in the excitation spectrum. Surprisingly, the roton dip and the corresponding peak in the depletion are enhanced by raising the temperature above absolute zero.



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