Article,
Universal properties of the ultracold Fermi gas
Physical Review A, (February 2009)
DOI: 10.1103/physreva.79.023601
Abstract
We present some general considerations on the properties of a two-component ultracold Fermi gas along the BEC-BCS crossover. It is shown that the interaction energy and the free energy can be written in terms of a single dimensionless function h(ξ,τ), where ξ=−(kFas)−1 and τ=T∕TF. The function h(ξ,τ) incorporates all the many-body physics and naturally occurs in other physical quantities as well. In particular, we show that the average rf-spectroscopy shift δω̅ (ξ,τ) and the molecular fraction fc(ξ,τ) in the closed channel can be expressed in terms of h(ξ,τ) and thus have identical temperature dependence. The conclusions should have testable consequences in future experiments.
