Adiabatic compression of soliton matter waves

The evolution of atomic solitary waves in Bose-Einstein condensate under adiabatic changes of the atomic scattering length is investigated. Variations of amplitude, width, and velocity of the soliton are found for both spatial and time adiabatic variations. The possibility of using these variations to compress solitons up to very high local matter densities is shown both in the absence and in the presence of a parabolic confining potential.