4-Channel Tunable Optical Demultiplexer Based on Nonlinearity Phenomenon in 2D Resonant Cavity Photonic Crystals

Abstract

AbstractIn this paper, we propose a new structure based on photonic crystals to realise a demultiplexing operation for dense wavelength division multiplexing transmission systems. In this demultiplexer, the resonant cavities were responsible for selecting the wavelength. By imposing defect rods to these cavities, the modes could resonate at the desired frequencies. As we wanted to see the nonlinear effects, the material that was chosen for defect rods were doped glass. The refractive index of this glass in 1550 nm is 1.41. Increasing the input power causes variation in the refractive index of defect rods and as a result resonant condition of whole cavity alerts so a tenable demultiplexer can be investigated. Based on the results, the average pass bands of channels are near to 1.5 nm and the channel spacing is approximately 3.95 nm. The proposed demultiplexer acts in a near-complete transmission efficiency and the mean value of the crosstalk was −19 dB.