CHARACTERIZATION OF PROTON-EXCHANGED AND ANNEALED PROTON-EXCHANGED PLANAR WAVE-GUIDES IN Z-CUT LINBO3

Mode index measurements of planar waveguides fabricated by proton-exchange and annealed proton-exchange in z-cut LiNbO3 have been made. A Fermi function was found to accurately model the index profile in a PE waveguide resulting in a better agreement between the measured mode indices and the computed dispersion curves compared to the conventional step-index profile. In addition, the effects of various fabrication parameters on the propagation characteristics of single-mode annealed proton-exchange waveguides have been investigated in detail. Such information will be useful in the analysis, design, and optimisation of devices to be fabricated with the proton-exchange and annealed proton-exchange technology.