Tuning characteristics of parametric interactions in a three-dimensional LiNbO3 optical waveguide

Abstract
Tuning characteristics of parametric interactions in a three‐dimensional LiNbO3 optical waveguide fabricated by a Ti in‐diffusion process are revealed by experimenting on both second harmonic and sum frequency generation. The experimental results agree well with the theoretical results, where Sellmeier’s equation and Marcatili’s approximation are used to evaluate the tuning characteristics of parametric interactions. The waveguide parameters are decided by the experimental phase‐matching temperature difference between the generated second harmonic fundamental and higher‐order modes.