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

I. E. Mazets·D. H. J. O'Dell·G. Kurizki·N. Davidson·W. P. Schleich
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Abstract

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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I. E. Mazets, D. H. J. O'Dell, G. Kurizki, N. Davidson, W. P. Schleich. 2004-01-28. Depletion of a Bose-Einstein condensate by laser-iduced dipole-dipole interactions. https://doi.org/10.1088/0953-4075%2F37%2F7%2F061

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