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arXiv · 1111.0035

Fast transitionless expansions of cold atoms in optical Gaussian beam traps

E. Torrontegui·Xi Chen·M. Modugno·A. Ruschhaupt·D. Guéry-Odelin·J. G. Muga
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Abstract

We study fast expansions of cold atoms in a three-dimensional Gaussian-beam optical trap. Three different methods to avoid final motional excitation are compared: inverse engineering using Lewis-Riesenfeld invariants, which provides the best overall performance, a bang-bang approach, and a fast adiabatic approach. We analyze the excitation effect of anharmonic terms, radial-longitudinal coupling, and radial-frequency mismatch. In the inverse engineering approach these perturbations can be suppressed or mitigated by increasing the laser beam waist.

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E. Torrontegui, Xi Chen, M. Modugno, A. Ruschhaupt, D. Guéry-Odelin, J. G. Muga. 2011-10-31. Fast transitionless expansions of cold atoms in optical Gaussian beam traps. https://doi.org/10.1103/physreva.85.033605

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