Bidirectionally Photoresponsive Optoelectronic Transistors with Dual Photogates for All‐Optical‐Configured Neuromorphic Vision

Abstract

Abstract Bio‐inspired neuromorphic vision sensors, integrating optical sensing, and processing functions have attracted significant attention for developing future low‐power and high‐efficiency imaging systems. However, the compulsory electrical signal modulation to achieve inhibitory behaviors in most reported neuromorphic vision sensors results in additional hardware and computational latency. Herein, bidirectional photoresponsive optoelectronic synapses based on In 2 O 3 /Al 2 O 3 /Y6 phototransistors are achieved, realizing all‐optical‐configured synaptic weight updates enabled by dual photogates. The inhibitory and excitatory photoresponses originate from the photogating effects provided by trapped photogenerated electrons in Al 2 O 3 under near‐infrared light and the ionized oxygen vacancies in In 2 O 3 under ultra‐violet light, respectively. The bidirectional phototransistor illustrates outstanding optoelectronic synaptic characteristics with low nonlinearity and asymmetry, demonstrating high efficiencies in both preprocessing and postprocessing tasks, such as noise reduction, contrast enhancement, and pattern recognition. The proposed dual‐photogate optoelectronic synapses provide effective strategies to construct high‐efficiency neuromorphic vision sensors and in‐sensor computing systems.