Anisotropic 2D diffusive expansion of ultra-cold atoms in a disordered potential

M. Robert-de-Saint-Vincent; J. -P. Brantut; B. Allard; T. Plisson; L. Pezzé; L. Sanchez-Palencia; A. Aspect; T. Bourdel; P. Bouyer

doi:10.1103/physrevlett.104.220602

arXiv · 1004.0312

Anisotropic 2D diffusive expansion of ultra-cold atoms in a disordered potential

M. Robert-de-Saint-Vincent·J. -P. Brantut·B. Allard·T. Plisson·L. Pezzé·L. Sanchez-Palencia·A. Aspect·T. Bourdel·P. Bouyer

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Abstract

We study the horizontal expansion of vertically confined ultra-cold 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{\deg} 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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M. Robert-de-Saint-Vincent, J. -P. Brantut, B. Allard, T. Plisson, L. Pezzé, L. Sanchez-Palencia, A. Aspect, T. Bourdel, P. Bouyer. 2010-04-02. Anisotropic 2D diffusive expansion of ultra-cold atoms in a disordered potential. https://doi.org/10.1103/physrevlett.104.220602

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