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Acoustic attenuation probe for fermion superfluidity in ultracold atom gases

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 نشر من قبل Sergio Gaudio
 تاريخ النشر 2005
  مجال البحث فيزياء
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 تأليف Sergio Gaudio




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Dilute gas Bose-Einstein condensates (BECs), currently used to cool fermionic atoms in atom traps, can also probe the superfluidity of these fermions. The damping rate of BEC-acoustic excitations (phonon modes), measured in the middle of the trap as a function of the phonon momentum, yields an unambiguous signature of BCS-like superfluidity, provides a measurement of the superfluid gap parameter and gives an estimate of the size of the Cooper-pairs in the BEC-BCS crossover regime. We also predict kinks in the momentum dependence of the damping rate which can reveal detailed information about the fermion quasi-particle dispersion relation.



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