Second-harmonic generation in hydrogenated amorphous Si(1-x)N(x) doubly resonant microcavities with periodic dielectric mirrors

We report on the realization of microcavities made of hydrogenated amorphous-Si1−xNx multilayers, with dual-wavelength periodic dielectric mirrors in order to obtain first and second order stop bands. Optical second-harmonic generation with simultaneous resonance for the pump and harmonic waves is demonstrated at finite values of the angle of incidence. The results are in good agreement with a theoretical calculation of the harmonic generation process based on a nonlinear polarization localized at the interfaces between different amorphous layers.