Abstract

It is known that optical beams can propagate unchanged in the form of self-guided waves or spatial optical solitons due to compensation of the beam diffraction by nonlinearity-induced change in the material refractive index [1]. Many of the properties of spatial optical solitons, including the stability analysis [2] and the inverse scattering technique [3], are unique for the Kerr materials when the nonlinear part of the refractive index n_nl(I) depends linearly on the light intensity I, n_nl(I) = n₂I, where n₂ is the so-called Kerr coefficient. However, since the first efforts to observe self-guidence and spatial solitons experimentally, in applications one deals with non-Kerr materials where the dependence n_nl(I) is not linear, e.g. it saturation. Recently it has been also shown, theoretically and experimentally, that self-guided beams can be observed in crystals with a strong photorefractive effect [4] and also due to phase-matched parametric interactions in a χ⁽²⁾ nonlinear medium [5,6]. In many cases, propagation of nonlinear waves in such non-Kerr materials are described by the nonlinear Schrödinger with a more general dependence of the refractive index on the beam intensity. The main purpose of this talk is to present a panoramic overview of different properties of solitary waves in nonKerr materials including the detailed discussion of the stability of (scalar and vector) bright and dark solitons and the soliton coupled states.

© 1996 Optical Society of America