Acoustic Attenuation Probe for Fermion Superfluidity in Ultracold-Atom Gases

Sergio Gaudio, Bogdan Mihaila, Krastan B. Blagoev, Kevin S. Bedell, Eddy Timmermans
2007 Physical Review Letters  
Dilute gas Bose-Einstein condensates (BEC's), 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
more » ... egime. We also predict kinks in the momentum dependence of the damping rate which can reveal detailed information about the fermion quasi-particle dispersion relation.
doi:10.1103/physrevlett.98.110407 pmid:17501033 fatcat:jm3isnojnfbtnc3jrzbyyysjqu