Electro-Opto-Thermal Dynamic Compact Model for Ring Modulator Arrays

Silicon photonic (SiPho) ring modulators (RMs) are widely used in optical transceivers due to their excellent electro-optic (EO) performance, small footprint, and low energy consumption. Because of the thermo-optic (TO) coefficient of silicon, these devices are sensitive to the changes in waveguide temperature. Simulation strategies that account for electrical, optical, and thermal effects simultaneously are hence of interest during the design stage of the device. In this work, a self-consistent, compact model is presented that is entirely SPICE-based and thus simple to implement. We build upon previous works and extend the simulation framework with the focus on thermal effects: 1) the addition of a thermal RC-networks for thermal tuning and for self-heating due to optical absorption and 2) a novel thermal crosstalk circuit element. The model demonstrates nonlinear self-heating effects at low frequency (<10 MHz), the simulation of thermal tuning and its impact on optical modulation, and finally large-scale thermal crosstalk and its mitigation strategies.