Numerical Simulation on Nonlinear Transmissive Characteristics of Fiber Bragg Grating

One-step system based on the semi-implicit Runge-Kutta method and simple iteration is designed for simplifying computation and avoiding the distortion of simulation results caused by shock response in solving a set of nonlinear coupled equations of fiber Bragg grating (FBG). The feasibility of the design is verified by comparing with other calculation methods and experimental results. The computational workload is greatly reduced when the same accuracy is required in simulating. Unified numerical simulation model based on physical process of optical wave transmission in grating is established under static and dynamic circumstances. Smoothing skills in simulation are researched. Nonlinear transmission characteristics of FBGs are studied numerically when continuous wave (CW) and pulse were input. The results show that the switching threshold power of phase-shift grating is lower than of uniform grating and all-optically tuned delay can be achieved by nonlinear effect in fiber Bragg grating.