Bias-reconfigurable barrier photodetectors for integrated broadband sensing and neuromorphic vision

Abstract

Intelligent vision systems demand photodetectors with reconfigurable response to support diverse modalities like high-speed sensing and neuromorphic processing. Here we show a bias-reconfigurable barrier photodetector that enables continuous modulation of response time across 7 orders of magnitude, from 614 ns to 8.28 s. This wide-range tunability is achieved by electrically modulating the interfacial barrier height, which switches the dominant carrier transport mechanism from direct tunneling to barrier-limited thermal excitation and trap-assisted processes. Under low bias, the device functions as a high-speed photodetector, whereas elevated biases extend the response to synaptic timescales, enabling in-sensor neuromorphic computing as a physical reservoir. Notably, the device exhibits a broadband photoresponse from visible to mid-infrared. High accuracy was achieved in complex recognition tasks, such as classifying vehicle acceleration or deceleration. This integration of fast photodetection and neuromorphic computation establishes hardware-efficient paradigms for integrated machine vision, adaptive multispectral sensing, and energy-efficient edge intelligence. Intelligent vision systems require diverse functionalities, ranging from high-speed sensing to neuromorphic processing. Wang et al. report a reconfigurable photodetector that seamlessly switches between these two operating modes, with its response time continuously tunable from nanoseconds to seconds.