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Fractal templates in the escape dynamics of trapped ultracold atoms

Kevin A. Mitchell·Daniel A. Steck
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Abstract

We consider the dynamic escape of a small packet of ultracold atoms launched from within an optical dipole trap. Based on a theoretical analysis of the underlying nonlinear dynamics, we predict that fractal behavior can be seen in the escape data. This data would be collected by measuring the time-dependent escape rate for packets launched over a range of angles. This fractal pattern is particularly well resolved below the Bose-Einstein transition temperature--a direct result of the extreme phase space localization of the condensate. We predict that several self-similar layers of this novel fractal should be measurable and we explain how this fractal pattern can be predicted and analyzed with recently developed techniques in symbolic dynamics.

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Kevin A. Mitchell, Daniel A. Steck. 2006-12-05. Fractal templates in the escape dynamics of trapped ultracold atoms. https://doi.org/10.1103/physreva.76.031403

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