Nonlinear dispersion equation and guided modes in a slab waveguide composed of a negative-index medium

We consider a slab waveguide made of a material with negative permeability and negative permittivity, the surrounding medium is conventional. By using the dispersion relation, we show the dispersion curves from the variation of the core width and other physical parameters. The associated energy flow for several thicknesses of the nonlinear layer waveguide is presented. We discuss possible new types of modes that can occur. It is found that the dispersion curves and the energy flow can be controlled by varying the thickness of the guide, the filling factor and the effective plasma frequency. A numerical simulation is done to well illustrate.