Design of Silicon Nitride Edge Coupler for Monolithically Integrated Laser on Silicon Photonic Circuits With Relaxed Alignment Tolerance and High Efficiency

We propose a bi-layer 5-tip edge coupler in multilayer silicon nitride-on-silicon (SiN-on-Si) waveguide platform. The is used for the integration between monolithic 1550 nm laser and single-mode SiN waveguide. simulated coupling efficiency 92.8%. vertical 1-dB-loss misalignment tolerance as large 0.5 μm. Broad 1-dB-drop bandwidth (1338 to 1700 nm) small footprint (total length: 38.2 μm) are achieved simultaneously. A broadband SiN-Si adiabatic transition cascaded designed couple power into Si at an of 90.6%. Low-computation-cost electromagnetic numerical simulation optimization strategies applied improve reverse design complex couplers.