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Complex scaling approach to the decay of Bose-Einstein condensates

Peter Schlagheck·Tobias Paul
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Abstract

The mean-field dynamics of a Bose-Einstein condensate is studied in presence of a microscopic trapping potential from which the condensate can escape via tunneling through finite barriers. We show that the method of complex scaling can be used to obtain a quantitative description of this decay process. A real-time propagation approach that is applied to the complex-scaled Gross-Pitaevskii equation allows us to calculate the chemical potentials and lifetimes of the metastably trapped Bose-Einstein condensate. The method is applied to a one-dimensional harmonic confinement potential combined with a Gaussian envelope, for which we compute the lowest symmetric and antisymmetric quasibound states of the condensate. A comparison with alternative approaches using absorbing boundary conditions as well as complex absorbing potentials shows good agreement.

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Peter Schlagheck, Tobias Paul. 2006-01-18. Complex scaling approach to the decay of Bose-Einstein condensates. https://doi.org/10.1103/physreva.73.023619

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