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arXiv · 0910.3387

Demkov-Kunike model for cold atom association: weak interaction regime

R. Sokhoyan·H. Azizbekyan·C. Leroy·A. Ishkhanyan
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Abstract

We study the nonlinear mean-field dynamics of molecule formation at coherent photo- and magneto-association of an atomic Bose-Einstein condensate for the case when the external field configuration is defined by the quasi-linear level crossing Demkov-Kunike model, characterized by a bell-shaped pulse and finite variation of the detuning. We present a general approach to construct an approximation describing the temporal dynamics of the molecule formation in the weak interaction regime and apply the developed method to the nonlinear Demkov-Kunike problem. The presented approximation, written as a scaled solution to the linear problem associated to the nonlinear one we treat, contains fitting parameters which are determined through a variational procedure. Assuming that the parameters involved in the solution of the linear problem are not modified, we suggest an analytical expression for the scaling parameter.

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R. Sokhoyan, H. Azizbekyan, C. Leroy, A. Ishkhanyan. 2009-10-18. Demkov-Kunike model for cold atom association: weak interaction regime. https://doi.org/10.3103/s1068337209060036

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