Experimental measurement of the effect of termination on surface electromagnetic waves in one-dimensional photonic bandgap arrays

Two different attenuated total-internal reflection prism configurations are used to explore the excitation of surface electromagnetic waves on one-dimensional (1-D) photonic bandgap (PBG) arrays. The effect of surface termination of the photonic crystal is shown to have a significant effect on the dispersion of the surface modes excited at that interface. The results show that it is possible to engineer the position of the surface mode within the forbidden bandgap. Modes that are located close to the center of the bandgap are shown to be more localized, leading to significantly higher surface electromagnetic fields than modes located near the band edge. The existence of surface modes can have an effect on many of the proposed applications for PBG materials. The modes are also of interest in their own right for use in applications such as sensors and modulators