Excitation of Phonons in a Bose-Einstein Condensate by Light Scattering
نویسندگان
چکیده
Stimulated small-angle light scattering was used to measure the structure factor of a Bose-Einstein condensate in the phonon regime. The excitation strength for phonons was found to be significantly reduced from that of free particles, revealing the presence of correlated pair excitations and quantum depletion in the condensate. The Bragg resonance line strength and line shift agreed with predictions for the homogeneous Bose gas using a local density approximation.
منابع مشابه
Direct observation of the phonon energy in a Bose-Einstein condensate by tomographic imaging.
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