2005/07/30 by J. Tempere, J. T. Devreese
Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #Condensed matter physics #Critical ionization velocity #Crossover #Lattice (music) #Optical lattice #Physics #Quantum mechanics #Quantum, superfluid, helium dynamics #Strong Light-Matter Interactions #Superfluidity #Trapping #cond-mat.other
paper · pdf · doi:10.1103/physreva.72.063601
published as Phys. Rev. A 72, 063601 (2005) · 12 pages, 3 figures
arxiv created 2005/07/30 · openalex publication_date 2005/12/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Both the trapping geometry and the interatomic interaction strength of a dilute ultracold fermionic gas can be well controlled experimentally. Adapting the interaction strength between the fermionic atoms allows tuning the gas from a molecular condensate to a Bardeen-Cooper-Schrieffer superfluid. We adopt a functional integral point of view to investigate how the superfluid properties vary during this crossover. In particular, the critical superfluid velocity for flowing through an optical lattice is derived. The observation of undamped motion in an optical lattice constitutes a hallmark of superfluidity, also in the fermionic systems. We discuss our theoretical results for the critical velocity of a fermionic superfluid in comparison to the experimental results for a bosonic superfluid in an optical lattice.