Peculiarities of resonance diffraction from periodic structures. Analytical approach

An overview in the report of results concerning diffraction by periodic structures under conditions of eigenmodes of the corresponding structure excitation surface polaritons or waveguide modes is presented here. The possibility of detailed analytical investigation of the problem is based upon the restriction with the case of weak scattering. When this restriction is made it is shown that resonance is strong. A simple analytical approach based upon modified perturbation theory allows presentation of results in explicit analytical form. We consider both the simplest geometry case (i.e., the wavevector of the periodic structure is parallel to the plane of incidence) and general geometry, and multiperiodic case, as well. The systematization of the resonances is presented for diffraction from the grating on the surface of high reflecting medium