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Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
Anisotropic 2D diffusive expansion of ultracold atoms in a disordered potential
M Robert-de-Saint-Vincent1, J-P Brantut, B Allard
1Laboratoire Charles Fabry de l'Institut d'Optique, Univ. Paris Sud, CNRS, campus polytechnique RD128, 91127 Palaiseau, France.
Abstract:
We study the horizontal expansion of vertically confined ultracold atoms in the presence of disorder. Vertical confinement allows us to realize a situation with a few coupled harmonic oscillator quantum states. The disordered potential is created by an optical speckle at an angle of 30° with respect to the horizontal plane, resulting in an effective anisotropy of the correlation lengths of a factor of 2 in that plane. We observe diffusion leading to non-gaussian density profiles. Diffusion coefficients, extracted from the experimental results, show anisotropy and strong energy dependence, in agreement with numerical calculations.
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