Propagation of electromagnetic waves in one dimensional symmetric and asymmetric Comb-like photonic structure containing defects

Abstract

In this paper, we study theoretically the transmission spectrum and the dispersion relation of a periodic photonic comb-like waveguide consisting of periodic segments of length d1 along which two different symmetric or asymmetric resonators of lengths d2 and d3 are grafted in each site. We study the presence of geometrical defects on the transmission spectrum. The creation of defects at the resonators levels of lengths d02 and d03 inside the perfect structure; enable to deduce the localized states (defects modes) inside the band gaps. In this research, we demonstrate the existence of two frequencies filtering with the presence of a single defect at the resonator level. In the same time, we investigate three frequencies filters in the existence of two defect resonators of lengths d02 and d03.