Spatial polarization instabilities due to transverse effects in nonlinear guided-wave systems

The elliptically polarized nonlinear beam propagation in a two-dimensional optical guided-wave system that contains isotropic Kerr media is solved numerically by using the finite-element method. Computed results for the nonlinear substrate exhibit novel transverse effects, such as spatial modulational instabilities for solitons emitted from the film. Since soliton emission can be interpreted in terms of self-induced Čerenkov radiation, these instabilities can be classified as Čerenkov instabilities. The sensitivity of the beam propagation to the initial state of polarization suggests the possibility of constructing new photonic devices.