Fitio V. Theory and analysis of optical diffraction phenomena on composite periodic structures

In this thesis the research results on interaction of electromagnetic waves with composite periodic structures are presented. An entire theory to describe such interactions on the basis of coupled-waves method (CWM) has been developed. This method has been improved by using symmetry owing to the diffraction effects. Numerical stable modified R and S-algorithms have been formulated. Based on CWM, a new fast method of 2D photonic crystal band structures calculation has been developed. Analytical expressions for analysis of multilayered holograms and the set of equations describing wave's propagation inside optic fibers with the Bragg's grating have been obtained. It is shown that a two-wave approximation can be used for nonlinear recording of thin holograms. Partly metalized gratings are analyzed with the help of CWM. It has been proved that either complete absorption or high transmission in narrow spectral band can be achieved as a result of electromagnetic field resonance. Analytical expressions have been fond, that connect the parameters of gratings or multilayered structures with electromagnetic field the parameters during resonance.