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arXiv · 1406.1327

Anisotropy in s-wave Bose-Einstein condensate collisions and its relationship to superradiance

Piotr Deuar·Jean-Christophe Jaskula·Marie Bonneau·Valentina Krachmalnicoff·Denis Boiron·Christoph I. Westbrook·Karen V. Kheruntsyan
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Abstract

We report the experimental realization of a single-species atomic four-wave mixing process with BEC collisions for which the angular distribution of scattered atom pairs is not isotropic, despite the collisions being in the $s$-wave regime. Theoretical analysis indicates that this anomalous behavior can be explained by the anisotropic nature of the gain in the medium. There are two competing anisotropic processes: classical trajectory deflections due to the mean-field potential, and Bose enhanced scattering which bears similarity to super-radiance. We analyse the relative importance of these processes in the dynamical buildup of the anisotropic density distribution of scattered atoms, and compare to optically pumped super-radiance.

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Piotr Deuar, Jean-Christophe Jaskula, Marie Bonneau, Valentina Krachmalnicoff, Denis Boiron, Christoph I. Westbrook, Karen V. Kheruntsyan. 2014-08-30. Anisotropy in s-wave Bose-Einstein condensate collisions and its relationship to superradiance. https://doi.org/10.1103/physreva.90.033613

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