PROPAGATION CHARACTERISTICS OF A NOVEL COMPLEMENTARY-STRUCTURE PLANARSEGMENTED WAVE-GUIDE

A new waveguide structure with periodically segmented cover and substr ate regions and a uniform film region is proposed. This complementary segmented waveguide is analysed in terms of the effective index and th e spot size of the guided mode, by expressing the propagating field as a linear combination of the local normal modes of the corresponding u niform slab waveguides in different propagation regions. The results m atch very well with those obtained using the equivalent waveguide mode l. The propagation loss of the mode of the proposed structure is calcu lated using a coupled mode approach, and the results are similar to th ose of a normal segmented waveguide. This waveguide structure should p rove useful in the realization of novel segmented waveguide devices. ( C) 1998 Elsevier Science B.V.