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Defect modes of a Bose-Einstein condensate in an optical lattice with a localized impurity

V. A. Brazhnyi·V. V. Konotop·V. M. Pérez-García
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Abstract

We study defect modes of a Bose-Einstein condensate in an optical lattice with a localized defect within the framework of the one-dimensional Gross-Pitaevskii equation. It is shown that for a significant range of parameters the defect modes can be accurately described by an expansion over Wannier functions, whose envelope is governed by the coupled nonlinear Schrödinger equation with a delta-impurity. The stability of the defect modes is verified by direct numerical simulations of the underlying Gross-Pitaevskii equation with a periodic plus defect potentials. We also discuss possibilities of driving defect modes through the lattice and suggest ideas for their experimental generation.

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V. A. Brazhnyi, V. V. Konotop, V. M. Pérez-García. 2006-03-31. Defect modes of a Bose-Einstein condensate in an optical lattice with a localized impurity. https://doi.org/10.1103/physreva.74.023614

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