All-Optically Controlled Positive and Negative Photoresponses for Artificial Visual Adaptation and Protection
In the era of artificial intelligence, efficient perception and processing of massive visual information demand advanced machine vision systems. Inspired by human visual adaptation, various optoelectronic devices have been developed, yet most rely on external gate voltages or complex circuits for dynamic sensitivity modulation. This work demonstrates an all-optically controlled biomimetic sensor based on a one-dimensional ZnO/MAPbBr3 heterojunction, achieving both positive and negative photoconductivity effects. By modulating oxygen vacancy states with ultraviolet light, the competition between intrinsic photoconduction and trap-mediated carrier capture is regulated, enabling dynamic control of visible-light photoresponse within a single device. This tunable behavior mimics scotopic adaptation (photopigment regeneration under weak illumination), photopic adaptation (photopigment bleaching in bright environments), and eyelid-like self-protection against intense light. The device operates without external gate bias or cascaded circuits, offering a promising strategy for next-generation intelligent biomimetic sensors in machine vision.