Higher-band gap soliton formation in defocusing photonic lattices

Abstract

We report on the experimental observation of higher-band gap solitons in a one-dimensional photonic lattice possessing a defocusing saturable nonlinearity. Pure Floquet-Bloch modes of the first three bands are excited using a prism-coupler setup, and spatial gap solitons of different width are formed, the latter property being related to the increasing anomalous diffraction in the three bands and the fixed value of the nonlinearity in our lithium niobate sample. © 2008 Optical Society of America.