Small multimode interferometer with simplified coherent coupling branches used to develop a lower footprint power splitter on silicon-on-insulator platform

Abstract

We introduced a innovative approach to fabricating a 1×2 power splitter under the silicon-on-insulator (SOI) platform, which can be scaled to a 1×N system device. The current design strategy is based on the well-known simplified coherent coupling, which allows for the construction of sharp bends. To split the incoming light, a small multimode interferometer (MMI) is added at the entrance of the splitter. Analysis and discussion regarding the sensitivity of the design parameters will be expanded throughout the paper. In addition, the proposed splitter architecture was fabricated and evaluated in 1×2 and 1×4 versions, and these devices were compared with splitters based on standard MMI also performed on the same SOI photonic chip. The splitter scheme demonstrates similar performance to standard MMI; however, a slight spectral flat response was observed in the new devices ensuring reliable operation across various wavelengths. This presented approach enables the design of highly compact devices, potentially opening different avenues to improve and enhance the performance of integrated devices developed under the SOI scheme.