Adiabatic invariant change due to separatrix crossing at sweeping through a Feshbach resonance in a nonlinear two-mode system.

Moдель демкова–кунике для ассоциации холодных атомов: режим слабого взаимодействия.

International audience; We examine the nonlinear dynamics of molecule formation at coherent photo- and magneto-association of an atomic Bose–Einstein condensate 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 an 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 adjustable pa…

The Demkov-Kunike model in the coherent magneto- and photoassociation of ultracold atoms.

Influence of the inter-particles elastic scattering on the quadratic-nonlinear Landau-Zener transition in photo- and magneto- association of ultracold atoms