Ultra-broadband multimode fiber-to-chip edge coupler based on periodically segmented waveguides

Mode-division multiplexing (MDM) technology demonstrates a bright outlook for enhancing the capacity of chip-scale or fiber-based optical communication. Nevertheless, the fiber-to-chip MDM optical interconnects are hindered by the considerable mode mismatch and inter-modal cross talk between the few-mode fiber (FMF) and on-chip few-mode waveguide (FMW). In this Letter, a new, to the best of our knowledge, multimode coupling solution based on periodically segmented waveguides for the MDM system is proposed, which achieves efficient conversion between LP