Josephson oscillation of a superfluid Fermi gas
نویسنده
چکیده
Using the complete numerical solution of a time-dependent three-dimensional mean-field model we study the Josephson oscillation of a superfluid Fermi gas (SFG) at zero temperature formed in a combined axially-symmetric harmonic plus one-dimensional periodic optical-lattice (OL) potentials after displacing the harmonic trap along the axial OL axis. We study the dependence of Josephson frequency on the strength of the OL potential. The Josephson frequency decreases with increasing strength as found in the experiment of Cataliotti et al. [Science 293 (2001) 843] for a Bose-Einstein condensate and of the experiment of Pezzè et al. [Phys. Rev. Lett. 93 (2004) 120401] for an ideal Fermi gas. We demonstrate a breakdown of Josephson oscillation in the SFG for a large displacement of the harmonic trap. These features of Josephson oscillation of a SFG can be tested experimentally. PACS. 03.75.Ss Degenerate Fermi gases, 03.75.Lm Tunneling, Josephson effect, Bose-Einstein condensates in periodic potentials, solitons, vortices, and topological excitations, 03.75.Kk Dynamic properties of condensates; collective and hydrodynamic excitations, superfluid flow
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