FDTD method to photonic waveguides for application of optical demultiplexer at 3-communication windows

Abstract

Present communication manipulates with 1-D photonic crystal waveguide to envisage optical demultiplexer by means of optical principle, which can effectively separate the three communication windows (850 nm, 1310 nm, 1550 nm). The proposed structure is envisaged through three photonic crystal waveguides, comprising of periodic arrangement of silicon (odd layer) and air (even layer). Further, finite difference time domain (FDTD) technique is employed to explore reflectance and absorption loss in the said photonic structures through band gap analysis. Simulation outcomes disclose that demultiplexing application relays on numerous factors such asthickness of various layers, nature of material, structure configuration, lattice constant etc of the proposed photonic waveguide. Moreover, it is seen that thickness of odd as well as even layers regulates band gap of the said waveguides, which leads to allow a particular wavelength and reject other wavelengths. Also, simulation upshots divulged that the first photonic crystal permits wavelength of 850 nm and rejects 1310 nm and 1550 nm for thickness of odd layer and even layer as 930 nm and 70 nm respectively. Similarly, the second photonic structure having odd layer thickness of 300 nm and 700 nm thickness for even layer, permits 1310 nm and rejects 1550 nm signal. Furthermore, for corresponding thickness of 980 nm and 20 nm for odd and even layer respectively, the third photonic structure allows wavelength of 1550 nmto pass through it. The aforementioned results declare that the suggested photonic structure can be apposite candidate for demultiplxer application in photonic integrated circuit.