Eur. Phys. J. D 48, 397-404 (2008)
https://doi.org/10.1140/epjd/e2008-00117-0

Two strong nonlinearity regimes in cold molecule formation

¹ Institute for Physical Research, NAS of Armenia, 0203 Ashtarak, Armenia
² Laboratoire de Physique Moléculaire et des Collisions, Université Paul Verlaine – Metz, 1 bd. Arago, 57078 Metz Cedex 3, France
³ Department of Physics, University of Turku, 20014 Turun yliopisto, Finland

Corresponding author: ^a artur@dolphin.am

Received: 26 August 2007
Revised: 7 April 2008
Published online: 13 June 2008

Abstract

Two distinct strongly non-linear scenarios of molecule formation in an atomic Bose-Einstein condensate (either by photoassociation or Feshbach resonance) corresponding to large and small field detuning are revealed. By examining arbitrary external field configurations, we show that the association process in the first case is almost non-oscillatory in time while in the second case the evolution of the system displays strongly pronounced Rabi-type oscillations. We construct highly accurate approximate solutions for both limit cases. We show that at strong coupling limit the non-crossing models are able to provide conversion of no more than one third of the initial atomic population. Finally, we show that for constant-amplitude models involving a finite final detuning the strong interaction limit is not optimal for molecule formation.