Study of titanium diffusion in lithium-niobate low-loss optical waveguides by x-ray photoelectron spectroscopy

Abstract
We have used x‐ray photoelectron spectroscopy to determine the valence of diffused titanium in LiNbO3. Our measurements show Ti ions only in the +4 valence state within the sensitivity of the measurement technique. Further analysis of our data indicates that the Ti ions occupy a unique site in the LiNbO3 unit cell.