Waveguide-Integrated Multifunctional Photodetectors for In-Sensor Computing

Emerging applications in the Internet of Things (IoT), autonomous vehicles, and robotics expose energy and latency bottlenecks in conventional photo-sensing based on the von Neumann architecture. In-sensor computing has emerged as a promising alternative by integrating multiple functions into a single device. 2D materials are widely used for prototypes owing to their excellent optoelectronic properties; however, free-space illumination poses several challenges. First, the limited light–matter interaction length-yields low absorption. Second, although logic and neuromorphic functions can combine electrical and optical signals, free-space coupling hinders dense interconnection. Finally, these applications often require infrared operation, which remains challenging for commonly used transition metal disulfides (TMDs). Here, we report a waveguide-integrated multifunctional photodetector for on-chip in-sensor computing that integrates light detection, nonvolatile memory, and reconfigurable logic/synaptic operations. Efficient infrared detection at 1552.5 nm is achieved, with a normalized photocurrent-to-dark-current ratio (NPDR) up to 6.4 × 10³ m W⁻¹. After negative control-gate pulses programming, the device exhibits a projected retention of 21.1% after 10 years. We further realize an “AND” logic and synaptic short- and long-term memory (STM/LTM). These results advance on-chip in-sensor computing compatible with high-density photonic-electronic interconnects and highlight a route toward systems that can sense, store, and compute at the point of capture.