Comprehensive model of MZI-based circuits for photonic computing applications

Photonic computing leverages the intrinsic advantages of photonic integrated circuits, including enhanced parallelism through wavelength, polarization, and mode division multiplexing, reduced power consumption, ultra-high operational speeds, and compatibility with silicon technology. We present a comprehensive circuit model for Mach-Zehnder interferometer (MZI) based meshed topologies, that is able to accurately predict the behavior of fabricated devices and that can be used for an efficient design of this kind of devices. Our proposed model incorporates both essential physical effects and parasitic phenomena, such as thermal crosstalk, that significantly influence device performance, thus enabling more realistic and accurate predictions of the device behavior, especially in densely integrated photonic circuits. By validating the model against the measured data of a fabricated device, we demonstrate its ability to reproduce the experimental evidence with high accuracy. Finally, we showcase the use of our approach in practical photonic computing scenarios, employing our model to program the MZI control voltages to implement specific logic functions on the reference device.