Hou, W.X.Chong, T.C.ELECTRICAL ENGINEERING2014-10-072014-10-071995Hou, W.X.,Chong, T.C. (1995). Characterization of proton-exchanged optical waveguides in ZnO:LiNbO3. Ferroelectrics, Letters Section 20 (3-4) : 119-125. ScholarBank@NUS Repository.07315171https://scholarbank.nus.edu.sg/handle/10635/80322We report the first demonstration of proton-exchanged optical planar waveguides in x-cut and z-cut LiNbO3 doped with 6 mol% ZnO using adipic acid as proton source. These waveguides exhibit a graded index profile which can be modeled by a linear step function with a surface index increase of 0.135 and 0.14 for x-cut and z-cut waveguides, respectively. The diffusion constant D0 and the activation energy Q are characterized optically to be 1.64×109 μm2/h and 88.8 KJ/mol for x-cut waveguides, and 1.478×109 μm2/h and 91.25KJ/mol for z-cut waveguides, respectively. The diffusion rate along the z-axis is slower than that along the x-axis, whereas the surface index increase on z-cut waveguides is larger than that on x-cut waveguides.ArticleNOT_IN_WOS