ИСТИНА

Dynamical Bragg diffraction of light in linear and nonlinear 1D photonic crystals (PCs) in the Laue scheme (Fig. 1) describes the effects originating from the interaction of the transmitted and diffracted waves during their propagation within the spatially-periodic structure and leading to a number of specific effects, such as the Borrmann phenomenon, pendulum effect, spatial and temporal pulse splitting [1,2]. At the Laue geometry of diffraction the incident wave splits into four waves that correspond to the two eigenmodes of the electromagnetic field inside a multilayer 1D PC, the so called Borrmann and anti-Borrmann optical modes. The first one is localized mostly inside the layers with smaller value of the refractive index, while the latter one – in those with larger refractive index. It was shown theoretically [3] that different combinations of these four waves can be used for effective phase-matching second harmonic generation (SHG) in periodic structures.