All-Silicon Non-Volatile Optical Memory Based on Photon Avalanche-Induced Trapping

Abstract Implementing on-chip non-volatile optical memories has long been an actively pursued goal, promising significant enhancements in the capability and energy efficiency of photonic integrated circuits. Here, we achieve this milestone by demonstrating optical memory exclusively using the most common semiconductor material, silicon. By manipulating the photon avalanche effect, we introduce a trapping effect at the silicon-silicon oxide interface, which in turn demonstrates a non-volatile reprogrammable optical memory cell with a record-high 4-bit encoding, robust retention and endurance. This silicon avalanche-induced trapping memory provides a distinctively cost-efficient and high-reliability route to realize optical data storage in standard silicon foundry processes. A proposed in-memory computing system achieves image recognition from the MNIST database with an inference accuracy of 94.8% and energy efficiency of 1.64×10¹³ MAC/J.