MATERIAL FIGURES OF MERIT FOR SPATIAL SOLITON-INTERACTIONS IN THE PRESENCE OF ABSORPTION

The effects of linear and two-photon absorption on bright spatial soli ton propagation are studied. A spatial soliton switch that achieves ga in through the novel mechanism of colliding, dragging, or trapping of two fundamental solitons of different widths is proposed. Figures of m erit for use in evaluating the suitability of absorbing nonlinear medi a for soliton switching applications are presented. The main effect of linear absorption is to limit the propagation distance, which places an upper bound on the width of the soliton in order to fit sufficient characteristic soliton propagation lengths within the device. The opti cal limiting nature of two-photon absorption places an upper bound on the gain that an interaction can achieve. The combined effects of line ar and two-photon absorption are to reduce the gain upper bound impose d by two-photon absorption alone with the addition of the soliton widt h constraint. A maximized gain upper bound is determined solely by mat erial parameters and is compared among three promising nonlinear mater ials. It is shown numerically that the spatial soliton dragging intera ction requires shorter propagation distances and achieves greater gain than the collision interaction and that both are tolerant to the pres ence of absorption and can provide, with high contrast, gains of three or greater using measured material parameters. These results warrant pursuing the implementation of spatial soliton-based logic gates. (C) 1996 Optical Society of America.