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Updated: Jun 23, 2026

Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
Extreme tunability of interactions in a 7Li Bose-Einstein condensate
S E Pollack1, D Dries, M Junker
1Department of Physics and Astronomy and Rice Quantum Institute, Rice University, Houston, Texas 77005, USA.
Abstract:
We use a Feshbach resonance to tune the scattering length a of a Bose-Einstein condensate of 7Li in the |F=1,mF=1> state. Using the spatial extent of the trapped condensate, we extract a over a range spanning 7 decades from small attractive interactions to extremely strong repulsive interactions. The shallow zero crossing in the wing of the Feshbach resonance enables the determination of a as small as 0.01 Bohr radii. Evidence of the weak anisotropic magnetic dipole interaction is obtained by comparison with different trap geometries for small a.
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