Resonant coupler based on Mach-Zehnder configuration

Optical couplers are important device in optical communication networks to perform coupling functionalities. Gathering several signals in one optical communication network is not the significant problem now due to the emergence of various inventions of optical couplers. Users can choose the best coupling technique to fulfill their requirement. Resonant coupler based on Mach-Zehnder configuration can enhance the performance of the coupling function with the advantages of low insertion loss, extremely low back reflection and precisely controllable wavelength that change only slightly with temperature. In this research, all of the related waveguide and the optimized design of resonant coupler were simulated by using Beam Propagation Method (BPM_CAD). The simulation result of parallel, S bend, and Mach-Zehnder configuration waveguide is used to get the optimize parameter with the best performance of resonant coupler. The design also needs to consider certain factor for practical application. The waveguides that form the resonant coupler consists of cascade between two directional coupler with one Mach-Zehnder configuration in the middle. It is designed so that the recombined signals will interfere constructively at one output and destructively at the other. Therefore, only the desired wavelength will emerge at the cross state output.