A two-step double ion-exchange process is employed to produce dual-core waveguides in glass. First, potassium ion exchange is carried out at 400°C. Then, silver ion exchange is performed at 300°C. The fabricated waveguides have low losses, large single-mode regions, and more symmetrical profiles than single ion-exchanged waveguides. Etched gratings are also made in dual-core waveguides. Very high efficiencies are demonstrated in these waveguides.

Natural Sciences and Engineering Research Council of Canada
Applied Physics Letters
Department of Electronics

Li, M.J. (M. J.), Honkanen, S. (S.), Wang, W.J. (W. J.), Leonelli, R. (R.), Albert, J, & Najafi, S.I. (S. I.). (1991). Potassium and silver ion-exchanged dual-core glass waveguides with gratings. Applied Physics Letters, 58(23), 2607–2609. doi:10.1063/1.104837