Superfluidity and phase transitions in a resonant Bose gas
Abstract
The atomic Bose gas is studied across a Feshbach resonance, mapping out its phase diagram, and computing its thermodynamics and excitation spectra. It is shown that such a degenerate gas admits two distinct atomic and molecular superfluid phases, with the latter distinguished by the absence of atomic off-diagonal long-range order, gapped atomic excitations, and deconfined atomic π-vortices. The properties of the molecular superfluid are explored, and it is shown that across a Feshbach resonance it undergoes a quantum Ising transition to the atomic superfluid, where both atoms and molecules are condensed. In addition to its distinct thermodynamic signatures and deconfined half-vortices, in a trap a molecular superfluid should be identifiable by the absence of an atomic condensate peak and the presence of a molecular one.
- Publication:
-
Annals of Physics
- Pub Date:
- October 2008
- DOI:
- 10.1016/j.aop.2008.05.008
- arXiv:
- arXiv:0711.0425
- Bibcode:
- 2008AnPhy.323.2376R
- Keywords:
-
- Condensed Matter - Superconductivity;
- Condensed Matter - Statistical Mechanics
- E-Print:
- 55 pages, 18 eps figures, submitted to Annals of Physics