High-Speed Optical Binary Neural Network Accelerator Enabled by Nonvolatile MEMS Phase Shifters for Edge AI Applications

This paper presents a novel approach for implementing Binary Neural Networks (BNNs) utilizing nonvolatile optical phase shifters. These phase shifters employ a micro-electromechanical system (MEMS) tuning mechanism, which enables the adjustment of the refractive index and phase of the propagating mode. In this approach, the weights of the BNN can be controlled by applying electrical signals to the phase shifters. Moreover, due to the nonvolatile operation of these devices, the network’s weights remain stable even when the electrical power source is cut off. The phases of the propagating modes, manipulated by the proposed phase shifters, determine the logic of the photonic circuit. The in-memory design of this device eliminates the need for network register banks, thereby significantly reducing resource usage, footprint, and power consumption. This approach offers much faster operation than other technologies, such as CMOS or spintronics, making it particularly appealing for edge artificial intelligence applications.