Chirped photonic crystal with different symmetries for asymmetric light propagation
In the present paper, we have carried out analysis of asymmetric light propagation in a chirped photonic crystal waveguide. The designed structures have hexagonal arrangement and square arrangement of silicon rods in air substrate. Dimensions of the defect rods are tailored, so that the proposed design structure works as an optical isolator. The transmission analysis of the structure reveals that it can act as an optical diode. We have plotted the extinction ratio and transmission analysis graphs for the structure, and it has been observed that the maximum output is obtained for telecom wavelength of 1.55 mm. Dispersion curves are obtained using the plane wave expansion method, and the transmission is simulated using finite element method. The proposed structures are applicable for photonic integrated circuits due to their simple and clear operating principle.