Reconfigurable optical arithmetic logic unit and its applications

The growing constraints of Moore's Law have fundamentally impeded further advancement in the energy efficiency of conventional electronic integrated circuits. In response, integrated photonics has emerged as a promising solution due to its exceptional bandwidth and ultralow latency. Optical digital computing based on integrated photonics offers inherent advantages in operation speed and energy efficiency compared to electronic digital schemes. However, implementing multi-functional arithmetic logic primitives on photonic chips still face a considerable challenge, and the reported works are mainly limited to basic logic gates or isolated computing modules rather than reconfigurable computational systems. Here, we report a reconfigurable optical computing architecture utilizing silicon-based microring modulators, which can implement reconfigurable basic logic operations and various arithmetic logic units, including 2-bit adder, subtractor and digital comparator. The experimental results demonstrate high computational density of 528 Gb/s/mm² and energy efficiency of 12.36 fJ/bit at the operation speed of 20 Gb/s. The proposed device's practical viability is further demonstrated through multiple application scenarios including data encryption and image processing.