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Modulational Instability in Bose-Einstein Condensates under Feshbach Resonance Management

Z. Rapti·G. Theocharis·P. G. Kevrekidis·D. J. Frantzeskakis
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Abstract

We investigate the modulational instability of nonlinear Schr{ö}dinger equations with periodic variation of their coefficients. In particular, we focus on the case of the recently proposed, experimentally realizable protocol of Feshbach Resonance Management for Bose-Einstein condensates. We derive the corresponding linear stability equation analytically and we show that it can be reduced to a Kronig-Penney model, which allows the determination of the windows of instability. The results are tested numerically in the absence, as well as in the presence of the magnetic trapping potential.

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Z. Rapti, G. Theocharis, P. G. Kevrekidis, D. J. Frantzeskakis. 2004-04-28. Modulational Instability in Bose-Einstein Condensates under Feshbach Resonance Management. https://doi.org/10.1238/physica.topical.107a00027

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