Optimization of WDM demultiplexer based on photonic crystal

In this paper, two-dimension band pass filters are proposed to design CWDM de-multiplexer which permit to separate two telecom wavelengths (1.31 μm and 1.55 μm). The square lattice with TE mode are adapted to designed the proposed de-multiplexer with help Photonic Band Gap (PBG). The structure has been designed using silicon rods, refractive index 3.45, which are embedded in air. The Plane Wave Expansion (PWE) method and 2D Finite Difference Time Domain (FDTD) method are employed to calculate the PBG range and output spectra of the filter. The localization property of photonic crystal has been used to guide the wavelengths in two different output with high transmission.