Mitigating Heating of Degenerate Fermions in a Ring-Dimple Atomic Trap

TL;DR

This paper investigates how a ring-dimple trap geometry reduces heating in a degenerate Fermi gas, with experimental results aligning with a model of background gas collision effects, aiding studies of fermionic superfluids.

Contribution

It demonstrates that a ring-dimple trap geometry can suppress heating in a degenerate Fermi gas, supported by experimental data and a collision-based heating model.

Findings

Heating rate is reduced in the ring-dimple trap with a halo.

Experimental heating rates agree with the hole-induced heating model.

Suppression of heating aids long-term fermionic superfluid studies.

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 non-degenerate "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 time scales is essential.