arXiv:0912.5379 · Physical Review A

Distortion of interference fringes and the resulting vortex production of merging Bose-Einstein condensates

Bo Xiong, Tao Yang, Keith A. Benedict

Published Oct 3, 2013• 17 citations

Abstract

We investigate the effects of interatomic interactions and expansion on the distortion of interference fringes of a pair of initially well-separated, but coherent, condensate clouds trapped in a harmonic trap. The distortion of interference fringes, which can lead to the spontaneous formation of vortices in the atom clouds, depends crucially on two relevant parameters: the center-of-mass velocity and peak density of the initial state. We identify three qualitatively distinct regimes for the interfering condensates: collision, expansion, and merging, by the spatial and temporal features of the fringe spacings. Using a comprehensive set of numerical simulations based on the Gross-Pitaevskii equation, we specify the crossovers between these regimes and propose the optimal system parameters required for dynamical instabilities and vortex creation.

DOI: 10.1103/physreva.88.043602

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