Fabrication of graded index profile in self-written waveguide by UV exposure method

In recent years, optical communication systems in a short distance become more important. We have studied a self-written waveguide technique as a promising optical interconnection technology. There are two problems in the self-written waveguide technique, which are the roughness on the side surface and transversely multi-mode waveguiding due to large core dimension. In this study, the refractive index distribution is managed with UV exposure method in order to resolve these problems. We succeeded in the control of cross-sectional refractive index distribution for the self-written waveguide. We suggest that self-forming waveguide has possibilities for the application.