2013/12/16 by Yangqian Yan, D. Blume · 13 citations
Physics and Astronomy · #Atomic and Subatomic Physics Research #Cold Atom Physics and Bose-Einstein Condensates #Condensed matter physics #Cooper pair #Fermion #Mechanics #Moment of inertia #Physics #Quantum #Quantum fluid #Quantum mechanics #Quantum, superfluid, helium dynamics #Superconductivity #Superfluidity #Vortex #cond-mat.quant-gas
paper · pdf · doi:10.1103/physrevlett.112.235301
published in Physical Review Letters 112(23), 235301 (American Physical Society) · 5 pages, 4 figures
arxiv created 2013/12/16 · openalex publication_date 2014/06/13 · arxiv updated 2014/06/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Superfluidity is a fascinating phenomenon that, at the macroscopic scale, leads to dissipationless flow and the emergence of vortices. While these macroscopic manifestations of superfluidity are well described by theories that have their origin in Landau's two-fluid model, our microscopic understanding of superfluidity is far from complete. Using analytical and numerical ab initio approaches, this Letter determines the superfluid fraction and local superfluid density of small harmonically trapped two-component Fermi gases as a function of the interaction strength and temperature. At low temperature, we find that the superfluid fraction is, in certain regions of the parameter space, negative. This counterintuitive finding is traced back to the symmetry of the system's ground state wave function, which gives rise to a diverging quantum moment of inertia I(q). Analogous abnormal behavior of I(q) has been observed in even-odd nuclei at low temperature. Our predictions can be tested in modern cold atom experiments.