Optical Pendellösung effect in 2D hexagonal photonic crystals based on porous anodic alumina

Intermodal light interference in artificial optical structures has become a powerful tool for precise routing of radiation. In periodic systems, it can lead to the Pendellösung effect consisting of the energy exchange between diffraction orders. Originally discovered for x rays, the optical analog of this phenomenon promises to be a viable means for the control of light. In this work, we investigate the Pendellösung effect in the visible spectral range in two-dimensional photonic crystals (PhCs) with a hexagonal lattice of pores in anodic alumina. We found peculiar spectral and angular variations of the light transmission near the Bragg diffraction conditions and provide a detailed analysis of the effect.