Gap solitons in optically induced two-dimensional square photonic lattices in LiNbO3:Fe crystals

Abstract

We fabricated two-dimensional square photonic lattices with a backbone structure in self-defocusing LiNbO3:Fe crystals through optical induction. We systematically observed four kinds of gap solitons and their power spectra in the nonlinear photonic lattices. Our results show that the lightwave is confined more tightly when it is launched into a low-index region at the input face of the crystal than when it is launched into a backbone ridge waveguide.