Pair collisions in a low-density fermi gas

Daniel Allman, Parth Sabharwal, Kevin Wright

We report on the impact of the extended geometry of a ring-dimple trap on particle-loss heating of a degenerate Fermi gas. When the Fermi level is slightly greater than the depth of the dimple and a broad, low-density ``halo'' is present, the overall heating rate is reduced relative to the case of a bare ring. We find that the experimentally measured heating rates for the overfilled dimple are in good agreement with a model of the hole-induced heating caused by background-gas collisions. This suppression of the heating rate can be helpful for experimental studies of fermionic superfluids in the weak pairing limit, where achieving and maintaining low temperatures over long timescales are essential.

John E. Thomas

Jordi Mur-Petit, A. Polls, M. Baldo +1 more

The possibilities of pairing in a low-density, cold Fermi gas interacting either through the interaction with another fermionic species or through a bosonic gas are analysed. In the latter case, special attention is devoted to the study of the experimentally relevant situation of a two-dimensional system. Estimates for the gaps at zero temperature in experimental conditions are presented.

E.L. Hazlett

Hans Feldmeier, P. Buck