A method and a system for nonlinear optical interaction in a nonlinear medium, comprising interacting at least one input beam in a nonlinear medium located at a spectrally dispersed plane. The method and system allows generating output photons from input photons, the output photons having properties that linearly depend on the properties of the input photons and that are mutually independent, comprising interacting the input photons in a nonlinear medium located at a spectrally dispersed plane.