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We analyze coherent anti-Stokes Raman scattering in thin-film dielectric waveguides. Extraordinarily large signal levels are predicted, and two applications of this phenomenon are discussed.

A normal mode analysis has been employed to calculate the transmission and reflection coefficients for a surface polariton propagating along the interface between a surface-active medium and a dielectric medium and crossing a boundary into a second dielectric medium. The efficiencies of conversion of the surface polariton into transmitted and reflected bulk waves of both s and p polarization are also investigated.

We calculate the efficiency with which a surface polariton at a metal-dielectric interface is excited when a p-polarized volume electromagnetic wave is incident upon the end face of the metal-dielectric system that is normal to the interface. We find generation efficiencies of approximately 90%

An interferometric technique for measuring with picosecond resolution the time evolution of the real and imaginary components of optical nonlinearities in channel waveguides is described. Characteristics of the technique are illustrated with measurements of band-filling optical nonlinearities in CdS(x)Se(1-x)-doped glass channel waveguides.

To test a model recently proposed to account for the observation of efficient second-harmonic generation in glass fibers, we have applied a strong dc electric field to the glass preform from which the fibers were drawn. We find that at most a temporary x(2) is induced, with a lifetime of a few minutes.

Two-photon absorption can place a fundamental limitation on waveguide all-optical switching devices. We have derived a general criterion to describe this limitation that must be satisfied by all materials. As a specific example, we have experimentally evaluated this criterion for a lead-glass fiber.

Dispersion measurements have been performed in optical fibers having a photoinduced refractive-index grating in the core. The results show that negative group-velocity dispersion can be obtained in these fibers over a frequency region of 500 MHz for wavelengths shorter than 550 nm.

We have derived and solved numerically the dispersion relations for waves guided by a thin metal film bounded on one or both sides by media with intensity-dependent refractive indices. Depending on the conditions, the usual two modes can be cut off and can undergo radical changes in their field distributions, and new modes can exist above certain power threshholds.

We show that physically realistic solutions for nonlinear TM waves guided by thin dielectric films are obtained in the uniaxial approximation for a dielectric constant proportional to the square of the normal-field component and not of the parallel-field component as assumed previously.

We analyze the parametric mixing of light by molecular monolayers deposited on a thin-film dielectric waveguide. It is shown that large signal levels are possible, even with cw lasers.

A simple inexpensive modulator based on a combination of the photorefractive and electrooptic effects in Ti:in-diffused LiNbO(3) waveguides is demonstrated.

We show that an optical pulse can propagate undistorted as a bright solitary wave in the normal dispersion regime when it couples through cross-phase modulation to a dark pulse in the anomalous dispersion regime.

We present numerical results showing the effects of a diffusive Kerr-type nonlinearity on the switching characteristics of a nonlinear directional coupler. It is found that switching can still occur even when the diffusion length is equal to the waveguide separation but that then its threshold increases and becomes less pronounced.

The beam-propagation method is employed to analyze nonlinear directional-coupler operation for various combinations nonlinear materials and initially mismatched guides. A mixed focusing-defocusing configuration is found optimal results.

The characteristics of prism coupling of finite-width beams into nonlinear waveguides composed of media with diffusive nonlinearities (thermal, etc.) are calculated by including a one-dimensional diffusion equation for the nonlocal nonlinearity. The resulting longitudinal feedback leads to bistability, and the threshold value for the minimum diffusion length varies inversely with the angular detuning.

Surface-plasmon polaritons guided by thin, lossy metallic films bounded by dissimilar dielectric media are investigated. New solutions to the dispersion relation are found, representing waves that are leaky (radiative) in one of the dielectrics. The new waves are interpreted in terms of the coupling of a damped surface plasmon at one interface with continuum modes at the other. Their excitation by end-fire coupling techniques is suggested.

A data acquisition system for high-resolution Fabry-Perot interferometry is described. Used in conjunction with a piezoelectrically scanned Fabry-Perot, this apparatus compensates for all frequency drifts, maintains interferometer alignment, and allows extended data acquisition times in selected regions of a spectrum.

Prism coupling of an argon laser into a nonlinear ZnS waveguide was investigated for power slew rates much less than the nonlinearity relaxation time. The angular variation in coupling efficiency becomes progressively more asymmetric with increasing power until switching occurs on one side of the curve. For large detunings on the switching side, increasing absorption bistability was observed.

We derive exact dispersion relations for transverse magnetic polarized guided waves at an interface between either a linear dielectric or a metal and a nonlinear dielectric. The nonlinearity is taken to be a Kerr-type nonlinearity. Numerical results are presented for the dielectric-metal case.

We have observed an intensity-dependent hysteresis in the transmission of guided waves through a thin-film waveguide with a cladding characterized by an intensity-dependent refractive index. Good agreement with theory was obtained.