From atomic to molecular Bose-Einstein condensates: a physically realizable term-crossing model for cold atom association.
Résumé
We study a nonlinear version of the Demkov-Kunike model, focusing on photoassociation of a Bose-Einstein condensate as a specific example. We show that the approximation describing time evolution of the molecular state probability both in the weak interaction limit and in the large detuning regime of the strong interaction limit can be written as a sum of two distinct terms; the first one, being a solution to a limit first-order nonlinear equation, effectively describes the process of the molecule formation while the second one, being the scaled solution to the linear Demkov-Kunike problem (but now with modified parameters), models the remaining oscillations which come up when the process of molecule formation is over.