Design and Simulation of Fiber Bragg Grating by Comsol Multiphysics Software

In this research, new software Comsol Multiphysics v.5.2 was used to study the mode distribution at the ends of step index optical fiber. Single mode Optical Fiber (SMF) and Multimode Optical Fiber (MMF) intensity distributions were presented in 2D Design. The modes in SMF were confined perfectly. Then, a 3D model of FBG was built on SMF with the same parameters of core and clad radius, refractive index of core and refractive index of clad. The most confined modes were appeared at 1550nm since this wave length is lossless in optical fiber. Increasing the periods of the grating inside the core will confined the modes at the transmission mode in the case of uniform Bragg grating.