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arXiv · 0804.3723

Coherent backscattering of Bose-Einstein condensates in two-dimensional disorder potentials

Michael Hartung·Thomas Wellens·Cord A. Mueller·Klaus Richter·Peter Schlagheck
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Abstract

We study quantum transport of an interacting Bose-Einstein condensate in a two-dimensional disorder potential. In the limit of vanishing atom-atom interaction, a sharp cone in the angle-resolved density of the scattered matter wave is observed, arising from constructive interference between amplitudes propagating along reversed scattering paths. Weak interaction transforms this coherent backscattering peak into a pronounced dip, indicating destructive instead of constructive interference. We reproduce this result, obtained from the numerical integration of the Gross-Pitaevskii equation, by a diagrammatic theory of weak localization in presence of a nonlinearity.

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Michael Hartung, Thomas Wellens, Cord A. Mueller, Klaus Richter, Peter Schlagheck. 2008-04-23. Coherent backscattering of Bose-Einstein condensates in two-dimensional disorder potentials. https://doi.org/10.1103/physrevlett.101.020603

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