Polychromatic interface solitons in nonlinear photonic lattices

We demonstrate that interfaces between two nonlinear periodic photonic lattices offer unique possibilities for controlling nonlinear interaction between different spectral components of polychromatic light, and a change in the light spectrum can have a dramatic effect on the propagation along the interface. We predict the existence of polychromatic surface solitons which differ fundamentally from their counterparts in infinite lattices.