Design and analysis of 2D photonic crystal based DEMUX using Y-shaped junction

Lithium niobate with its electro-optic properties is used as dielectric rods arranged in a 15 × 13 square lattice within an air medium to simulate and develop a two-dimensional optical demultiplexer (DEMUX) based on photonic crystals (PhCs). To steer light, a Y-shaped line defect is added, which serves as a 1 × 2 DEMUX. Using an eigenfrequency-based analysis, the structure’s photonic bandgap (PBG) is determined to be a bandgap between the first and second bands in the frequency range of 2.1188 × 10 14 Hz to 2.4604 × 10 14 Hz. A wave optics model is used to study the transmission characteristics in the 1.55 µm–1.60 µm operational wavelength range. Effective input and output light routes are made possible by the inclusion of line defect faults. The finite element method (FEM) is used to generate field profiles, and S-parameter analysis sheds light on power flow and signal behavior at various ports. Electric (E) and magnetic (H) field distributions are recovered by periodic port analysis; resonances are detected at 1.5359 µm with peak transmissions of 0.49 achieving 50 % and quality factors of 1,097, respectively. The design is appropriate for wavelength-selective switching applications like splitters and all-optical switches in elastic optical networks (EONs) due to its low crosstalk, low reflection, and efficient wavelength separation.