Novel Spatial Solitons in coupled Lithium Niobate Waveguides by Reverse Proton Exchange

A. Di Falco and G. Assanto

IEEE Photon. Techn. Lett. 15, 537-539 (2003)


We numerically investigate a novel type of quadratic spatial solitons in the system of surface and buried planar waveguides obtained via direct- and reverse-proton-exchange in z-cut Lithium Niobate, respectively, and coupled by the second-order susceptibility. Through frequency doubling, TE and TM modes lock into a 1+1D solitary wave encompassing orthogonal field components at the two harmonic wavelengths. The phase matching scheme leads to a wavelength-comb filter with adjustable linewidths.