S-polarized waves in a thin dielectric film asymmetrically bounded by optically nonlinear media

This paper contains a comprehensive theory, supported by many numerical examples, of the behavior of electromagnetic waves in a potential device that consists of a thin, opticaliy linear film, bounded by dissimilar semiinfinite nonlinear materials with frequency- and wavenumber-independent parameters. The relationship between the electric field amplitudes on the respective boundaries of the film leads to an elegant analysis that results in physical quantities being derived without a quantitative knowledge of the nonlinear fields. Guided and surface waves are precisely differentiated from each other, and it is shown that the linear cutoff criterion generalizes, when nonlinearity is added, to a novel changeover condition. The nonlinear eigenvalue equations are used to give the guided/surface mode index in terms of the optical power density at one of the interfaces. The power flow down the guide is then calculated both as a function of the interfacial optical power density and as a function of the mode index. These are shown to lead to two different sets of dispersion curves labeled with power flow down the guide or the optical power density at the interface. Finally, by assuming that the nonlinear media are lossy, optical hysteresis is shown to be possible.