Bright spatial soliton dynamics in a symmetric optical planar waveguide structure

The behavior of spatial solitons in coupled planar optical waveguides is investigated. A full derivation of the appropriate coupled nonlinear Schr\"odinger equations is given that includes all the nonlinear cross-phase modulation terms. The dynamics of the spatial solitons are developed using the average variational method of Whitham $[---Linear and Nonlinear Waves (Wiley, New York, 1974)]. The main problems addressed concern spatial soliton beam displacement, beam switching, and a few stability problems. Significant mathematical progress has been made, which is also verified by accurate numerical simulations.