Manipulation of optical solitons in Bose-Einstein condensates

We propose a method to control the optical transparency of a Bose-Einstein condensate with working energy levels of the Λ-type. The reported effects are essentially nonlinear and are considered in the framework of an exactly solvable model describing the interaction of light with a Λ-type medium. We show how the complicated nonlinear interplay between fast and slow solitons in the Λ-type medium points to a possibility to create optical gates as well as to a possibility to store optical information