With insights of the Purcell effect for controlling the optical nonlinearity of the device through phase damping, this invention uses nanostructured, solid, nonlinear material which is less than about 10 nm, which can be operated at a temperature of less than about 77 Kelvin, and which electronic bandgap is at least twice as large as an energy of a photon. The invention also includes dielectric structures around the nonlinear material providing a photonic band gap that partially overlaps the electronic bandgap of the nonlinear material. Furthermore, a waveguide is included in the invention which is disposed at the dielectric structure to couple light to the nonlinear material and direct processed light away from the nonlinear material. This system enables a wide range of optical device operations and configurations with operational capabilities not previously attainable. All-optical signal processing devices having operating powers and switching times that are orders of magnitude smaller than those corresponding to traditional nonlinear optical devices are thus attainable.