Single port tunable DWDM demultiplexer using two-dimensional Photonic crystal

This paper discusses a tunable optical filter designed using the two-dimensional (2D) photonics crystal square lattice (PCSL). The filter has been designed to work in Dense Wavelength Division Multiplexing (DWDM) communication using rectangle resonant cavity. The filter analysis was initially carried out by changing the attributes of photonic crystal such as the radius of inner ring pillars and refractive index. Hence, it is possible to tune the wavelengths with characteristics according to ITU.T G.6941 DWDM standard. The filter is designed to work in 1551 nm, 1552 nm, 1553 nm, 1554 nm, 1555 nm, and 1556 nm with 1nm channel spacing and 0.8 nm spectral linewidth, 96 % to 100 % transmission efficiency, and quality factor to be 2000 respectively. The proposed filter was designed and simulated with Finite-Difference Time-Domain (FDTD) algorithms, and the results are discussed at the end for the use in Photonic Integrated Circuits.