Accurate EO co-simulation of Si photonics using a standard electronic circuit simulator

Co-packaging and integration of photonics and electronics has been recognized as a promising solution for the next-generation optical interconnects beyond terabits per second. To accurately verify and predict the performance of integrated transceivers, Electro-Optic (EO) co-simulation, including both optical and electrical devices, is essential. An effective co-simulation method is importing photonic models into electronic circuit simulators using hardware modeling language such as Verilog-A. However, conventional Verilog-A-based photonic device models lack fidelity in capturing physical characteristics such as RF characteristics, nonlinearity, noise, and process variations, resulting in significant discrepancies between measurements and simulations. Here, we developed a model library for accurate EO co-simulation in high-speed transceiver design. Si photonics devices and associated test equipment were carefully modeled based on experiments. The simulation results using the developed models showed excellent agreement with measurements up to 40 GHz and 64 Gbaud, demonstrating the fidelity of EO co-simulation for Si photonics transceiver design. The models and sample test benches will soon be available as an open-source library on GitHub.