부산대학교 도서관

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jnoncrysol.2008.04.052 Byline: L.A Azcan (a), Francis Guay (a), Raman Kashyap (a)(b), Ludvik Martinu (a) Keywords: Dielectric properties, relaxation, electric modulus; Planar waveguides; Chemical vapor deposition; Laser-matter interactions; Photoinduced effects; Germania; Silica Abstract: A CW CO.sub.2 laser ablation technique is used to form buried waveguides in planar silica films. It is shown that the refractive index of a silica thin film is reduced sufficiently adjacent to the laser processed region to allow the fabrication of low loss waveguides. The refractive index distribution of these structures is measured using the reflectance of a focussed spot from the surface of the films. The change in refractive index is measured to be of the order of the core cladding refractive index difference of typical single mode waveguides. The spatial resolution of the reflectance technique is 1.3[mu]m with a refractive index resolution of [+ or -]5x10.sup.-4. Devices such as 1x2 and 1x4 multi-mode interference (MMI) splitters have also been demonstrated and shown to exhibit low transmission losses. Author Affiliation: (a) Department of Engineering Physics, Ecole Polytechnique de Montreal, P.O. Box 6079, Station Centre-ville, Montreal, Quebec, Canada H3C 3A7 (b) Department of Electrical Engineering, Ecole Polytechnique de Montreal, P.O. Box 6079, Station Centre-ville, Montreal, Quebec, Canada H3C 3A7