Dynamics of the Bose–Einstein condensation

Bose–Einstein condensation is a very general physical phenomenon which takes place not only in the systems of bosonic atoms, but also in optical wave systems. Many important features of the condensation in such diverse systems can be captured by the nonlinear Schroedinger model. Within this model we develop a statistical description in which the condensate is nonlinearly coupled to wave turbulence described by a kinetic equation. Our focus will be on the strong-condensate regime in which the three-wave interaction replaces the four-wave process operating on the preceding stages of an explosive condensate formation and its initial growth. In the strong-condensate regime, the condensate growth accelerates and becomes quadratic in time. This regime will proceed until the wave dispersion drops below a critical value and the state of dispersionless acoustic turbulence forms.