Ultrasensitive dim-light neuromorphic vision sensing via momentum-conserved reconfigurable van der Waals heterostructure.

Reconfigurable phototransistors featuring bipolar photoresponses are favorable for manipulating high-performance neuromorphic vision sensory. Here, we present a momentum-conserved reconfigurable phototransistor based on the van der Waals heterojunction between methylammonium lead iodide perovskite and two-dimensional Bi₂O₂Se semiconductor, which exhibits a synergistic interplay of interband hot-carrier transitions and reconfigurable heterointerface band alignments, eventually achieving the ultrahigh bipolar optoelectronic performances with the photoresponsivity of 6×10⁷ AW⁻¹, accompanied by the specific detectivity of 5.2×10¹¹ Jones, and the dynamic range of 110 dB. Moreover, A 3×3 heterotransistor array is fabricated to perform in-sensor analog multiply-accumulate operations even under the challenging dim illumination of 0.1 μWcm⁻² that comparable to natural moonlight. The reconfigurable heterotransistor array can be further adopted to enhance the traffic-light detection under dim-light conditions. Our advancement in momentum-conserved reconfigurable heterotransistor signifies a leap forward in real-time, energy-efficient, and low-light image processing for neuromorphic vision sensors. Xu et al. report reconfigurable phototransistors based on MAPbI₃/Bi₂O₂Se heterostructure, with momentum conservation promotes hot carrier extraction and interlayer carrier transport. Heterotransistor array enables traffic light signal detection under dim light, assisted by YOLOv4 neural network. [ABSTRACT FROM AUTHOR]