Raman spectra of proton-exchanged LiNbO3 optical waveguides

Based on the Raman spectrum measurement, we investigate the mechanism of proton exchange, by which the optical waveguides are formed in the LiNbO3 crystal which are proton doped. The proton source is formed by a mixture of benzoic and adipic acids. The experimental results show that there is a Raman formant peak of optical waveguide at 650 cm(-1), and the higher the relative percentage of the mol ratio of adipic acid dilution, the higher the intensity of the Raman formant peak.