Design of Photonic Crystal Triplexer with Core-Shell Rod Defects

We investigate an optical compact triplexer based on two photonic crystal waveguides and resonant cavities. For performing wavelength selection, we use three core?shell rods as the resonant cavities. The core rods are created by introducing air holes in the center of the silicon rods. By varying the radii of the air holes, three specific wavelengths 1.31, 1.49 and 1.55 μm can be obtained. This structure is designed and its performance is verified by the finite-difference time-domain method, which is highly suitable for photonic integrated circuits (PICs). The average output transmission efficiency and quality factor are more than 98.85% and 560, respectively. The mean value of the crosstalk between output channels is about -36.49 dB. The present device is extremely compact with total size 96.24 μm², which is suitable for PICs and can be utilized in the fiber-to-the-home system.