Resonant enhancement of electromagnetic wave in the structure with refractive index gradient

Propagation of electromagnetic wave (EW) through graded refractive index material is studied theoretically. Green´s function technique used to obtain the solution of Maxwell equation in the gradient region for the nonzero angle of incidence wave. Results of our calculations show a resonant increase in the amplitude of EW waves for a certain frequency. We studied effects of the size and profile of gradation region on the position (frequencies) of the resonances.