Solitary wave propagation and bistability in the normal dispersion region of highly nonlinear optical fibres and waveguides

Properties of bright solitary wave solutions of the cubic-quintic nonlinear Schrodinger equation are considered in the normal dispersion region of optical fibres and waveguides with third-and fifth-order nonlinearities. The case of an optical fibre is concretely considered but other possible waveguide geometries are also discussed. For comparison, the properties of the black solitary wave existing in the same parameter range are also considered. All soliton parameters are presented in a unified way as functions of the normalised pulse energy. The possibility for bistable behaviour of the solitary waves is examined and a new type of solitary wave bistability (bright-dark) is introduced. The role of the geometry of the waveguide and the appropriate materials for experimental observation of such waves are also discussed. (C) 1997 Elsevier Science B.V.