Two species superfluid Fermi gas is investigated on the BCS side up to the Feshbach resonance. Using the Greens's function technique gradient corrections are calculated to the generalized Thomas-Fermi theory including Cooper pairing. Their relative magnitude is found to be measured by the small parameter (d/RTF)4, where d is the oscillator length of the trap potential and RTF is the radial extension of the density n in the Thomas-Fermi approximation. In particular, at the Feshbach resonance the universal corrections to the local density approximation are calculated and a universal prefactor κW=7/27 is derived for the von Weizsäcker-type correction κW(2/2m)(2n1 2/n1 2).
|Journal||Physical Review A - Atomic, Molecular, and Optical Physics|
|Publication status||Published - Dec 8 2010|
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics