Stability of trapped Bose-Einstein condensates - art. no. 043604

In three-dimensional trapped Bose-Einstein condensate (BEC), described by t he time-dependent Gross-Pitaevskii-Ginzburg equation, we study the effect o f initial conditions on stability using a Gaussian variational approach and exact numerical simulations. We also discuss the validity of the criterion for stability suggested by Vakhitov and Kolokolov. The maximum initial chi rp (initial focusing defocusing of cloud) that can lead a stable condensate to collapse even before the number of atoms reaches its critical limit is obtained for several specific cases. When we consider two- and three-body n onlinear terms, with negative cubic and positive quintic terms, we have the conditions for the existence of two phases in the condensate. In this case , the magnitude of the oscillations between the two phases are studied cons idering sufficient large initial chirps. The occurrence of collapse in a BE C with repulsive two-body interaction is also shown to be possible.