Novel polymer-based resonant grating-waveguide structures

Summary form only given. The basic configuration of grating waveguide structures (GWS) is composed of a thin dielectric or semiconductor waveguide layer, and an additional transparent layer in which a grating is etched. When such a GWS is illuminated with an incident light beam, most of the beam is directly transmitted while the rest is diffracted, trapped in the waveguide layer, and subsequently, partially rediffracted outwards. At a specific resonant wavelength and angular orientation of the incident beam the rediffracted beam interferes with the transmitted beam, so that the incident beam is completely reflected from the GWS. Extremely narrow resonance bandwidths of about 0.1 nm and modulation of 10 MHz were already achieved with active GWS, suggesting that they could be very attractive in optical communication systems as spectral filters and switches. So far, GWS have been mainly based on semiconductor materials that are both rather difficult to fabricate and costly. We present, a new approach based on the replacement of semiconductor materials by advanced polymeric materials expected to lead to GWS that can be readily fabricated at a low cost, so that they can be attractive as photonic devices for the WDM optical communication systems.