Abstract

In a Kerr-medium stable spatial solitons or self-trapped beams can exist only in two-dimensional geometries as in planar waveguides, where the diffraction is limited to one spatial dimension. However, in a medium with a saturable nonlinear refraction index change Δn(I) the rate at which a beam tends to focus is restricted, therefore diffraction will counter balance the self-focusing for a critical intensity preventing the beam collapse. Recently photorefractive materials have been used as a medium with saturable nonlinearity to generate spatial solitons as well in (1 +1) as in (2+1) dimensions [1].

© 1996 Optical Society of America