Optical Sciences

We calculate the power-dependent propagation constant of a surface-plasma wave as a function of the thickness of the metal film on which it propagates when the metal film is bounded by a nonlinear semiconductor. In the case of a Cu film bounded by InSb at a wavelength of ~5 ...

We investigate the dispersion of the group velocity of light in slab and rectangular waveguides and obtain analytic expressions for the first derivative of the propagation vector with respect to the angular frequency and numerical values for the second derivative for both geometries. The last quantity is an important parameter in the temporal soliton propagation equation, which motivates this research. Provided the dispersion within the channel can be adjusted properly, planar geometry waveguides can represent good candidates for the optical processing of temporal solitons carried by optical fibers. We discuss the manner in which the dispersion coefficient depends on waveguide dimensions and material constants, and we determine the parameters that optimize soliton processing.

In this paper, we consider a layered structure consisting of dielectric, metal, and dielectric media and compute the fields produced in the structure by a finite width beam of incident radiation which couples to a longrange surface-plasmon mode in the metallic layer. The analysis allows for complex dielectric constants in all media and focuses on optical radiation. Curves are presented which show the profiles of the reflected field intensity for different values of the propagation length of the mode relative to the width of the incident beam. We discuss the conditions in which the field reradiated from the long-range surface mode can interfere with the specularly reflected radiation so as to produce an interference zero in the reflected profile. In these conditions our analysis allows for a determination of the separate loss coefficients of the mode associated with energy reradiation and dissipation, respectively Robert Deck is with University of Toledo, Department of Physics & Astronomy, Toledo, Ohio 43606; J. M. Elson is with U.S. Naval Lake, California 93555; the other authors are

We show theoretically that by use of a new coupling geometry the second-harmonic light generated at the surface of a thin metal film can be enhanced dramatically through a coupling of the fundamental field to a long-range surface-plasmon mode. The resulting reflected harmonic intensity is predicted to be more than 2 orders of magnitude larger than that obtainable in the standard Kretschmann or Otto geometry.

We address the theory of temporal soliton switching in a planar geometry directional coupler constructed from silica and doped silica glass and operating at the central wavelength of 1.55 m, significant for erbium-doped amplification. We formulate the field in the coupler in terms of the supermodes of the total structure and take account of the two transverse dimensions of the rectangular channels. In the case of the weak coupling between channels consistent with elimination of pulse breakup, the effect of the fields in the outer corner regions of the channels results in a switching intensity that differs significantly from that derived from coupled-mode theory on the basis of a slab model of the coupler.