Multichannel switchable system for spatial solitons

A simple model of a nonlinear planar waveguide with a periodic modulation of the refractive index in the transverse direction was considered which gives rise to a system of parallel channels. The model may also describe a densely packed planar array of parallel nonlinear optical fibers. By means of the variational approximation and by direct simulations, it is demonstrated that the one-soliton state trapped in a channel has no existence threshold and is always stable.