Nonlinear surface 2D plasmons and giant second harmonic generation

Surface plasmonics and plasmonic metamaterials became very popular in connection with new promising applications for transmission lines subwavelength optics, sensors etc., from THz to optical frequencies. In the present paper, giant localized second harmonic generation under condition of only temporal (not spatial) resonance of nonlinear surface plasmons and quasi-soliton excitations are considered. The general method for the derivation of evolution equation in the layered nonlinear structures with surface and volume nonlinearities is developed and an importance of surface nonlinearity in the mentioned above nonlinear processes is addressed. Conditions of experimental observations of nonlinear phenomena in different structures, including plasmonic metamaterias, are discussed.