Second- and third-harmonic generation in birefringent photonic crystals and microcavities based on anisotropic porous silicon

Abstract

The technique of fabrication of one-dimensional anisotropic photonic crystals and microcavities based on porous silicon with birefringence has been developed. The spectra of linear reflectance demonstrate presence of photonic band gap (PBG) and microcavity mode located in the center of PBG. Their spectral position is tuned upon the sample rotation around its normal and/or rotation of incident light polarization plane. Enhancement of second- and third-harmonic generation for the fundamental wavelength resonant to the long wavelength edge of PBG due to phase matching is observed by angular spectroscopy. The angular positions of second- and third-harmonic peaks are determined by porous silicon dispersion and shifted for different polarisation of the fundamental wave due to the dielectric function anisotropy.