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

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° 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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Cited by in corpus (5)

• Coherent Backscattering of Ultracold Atoms
• Bogoliubov Excitations of Disordered Bose-Einstein Condensates
• Localization of Bogoliubov quasiparticles in interacting Bose gases with correlated disorder
• Momentum isotropisation in random potentials
• Localization of an inhomogeneous Bose-Einstein condensate in a moving random potential