Abstract
A three-component Fermi gas near a broad Feshbach resonance does not have a universal ground state due to the Thomas collapse, while it does near a narrow Feshbach resonance. We explore its universal phase diagram in the plane of the inverse scattering length and the resonance range . For a large , there exists a Lifshitz transition between superfluids with and without an unpaired Fermi surface as a function of . With decreasing , the Fermi surface coexisting with the superfluid can change smoothly from that of atoms to trimers (“atom-trimer continuity”), corresponding to the quark-hadron continuity in a dense nuclear matter. Eventually, there appears a finite window in where the superfluid is completely depleted by the trimer Fermi gas, which gives rise to a pair of quantum critical points. The boundaries of these three quantum phases are determined in regions where controlled analyses are possible and are also evaluated based on a mean-field plus trimer model.
- Received 30 July 2012
DOI:https://doi.org/10.1103/PhysRevLett.109.240401
© 2012 American Physical Society