Topology design of reconfigurable power splitter with pixelated Sb-based phase change materials

The waveguide-integrated reconfigurable power splitting is of great importance for on-chip all-optical connec-tion. Based on the combination of silicon and Sb-based phase change materials (PCMs), a series of ultra-compact reconfigurable power splitters is topologically designed. The footprints of the functional regions are kept less than 1.0 lambda 2. The power splitting ratio between the output channels can be reconfigured through the amorphous and crystalline switching of Sb-based PCMs. We demonstrate Sb2Se3-based and Sb2S3-based digital metamaterials for the reconfiguration between power splitting ratio of 5:5 and power splitting ratios of 5:5, 6:4, 7:3, 8:2 and 9:1. The three-dimensional FDTD simulations show that the targeted power splitting ratio can be achieved with acceptable precision. Moreover, the robustness of design is validated by introducing pixel errors.