Mitigating heating of degenerate fermions in a ring-dimple atomic trap

Abstract

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.