Electromagnetic scattering by the two-dimensional photonic crystals with periodic defects

Efficient and accurate method to characterize twodimensional electromagnetic scattering from multilayered periodic arrays of cylindrical objects with periodic defects applying Lattice Sums technique and T-matrix approach is presented. The proposed method is used to analyze the effects of periodic defects on the frequency response in reflectance from multilayered arrays of circular cylinders and the array embedded in the dielectric slab. The method is quite general and applies to various configurations of two-dimensional periodic arrays. The power reflection coefficient is numerically studied and the influence of the periodic spacing of cylinders on the power reflection coefficient is discussed. The results demonstrate various interesting features of the frequency response in the multilayered grating with periodic defects, which are not available when the periodic spacing of cylinders along each array plane is the same over all layers. The numerical simulations have shown that the convergence of the proposed method is fast and accuracy of calculation is high.