Effects of water vapor on refractive index profiles in Ti:LiNbO3planar waveguides

A systematic investigation on the effects of water vapor during Ti:LiNbO
3
waveguide fabrication is reported, including optical and spectroscopic analysis. Extraordinary index profiles are changed by the presence of H
2
O in the diffusion atmosphere, while outdiffused waveguides are not suppressed. The resulting profiles cannot be explained by a simple change of the Ti diffusion coefficient, and more complex models should be developed to describe the phenomena.