Optoelectronic Resistive Memory Based on Lead-Free Cs2AgBiBr6 Double Perovskite for Artificial Self-Storage Visual Sensors

Abstract

Mimicking the human visual memory system has attractive prospects in the field of artificial vision. However, the prominent challenge of realizing human visual memory is how to detect and store image information at the same time, which demands a multifunctional electronic device that can sense and memorize image information like the brain. In this work, simple two-terminal optoelectronic resistive random access memory (ORRAM) devices are demonstrated based on lead-free Cs2AgBiBr6 perovskite, exhibiting a unique optoelectronic resistive characteristic that can be reset by UV light illumination. A proof-of-concept artificial self-storage visual system based on the ORRAM is constructed, which shows similar reinforcement learning and memory forgetting functions to the human visual memory system, and realizes the integrated functions of image sensing and memory for a long-term retention time (>6000 s). Theoretical calculations indicate that UV light illumination will induce the annihilation of Br defects and cause the fracture of conductive filaments, resulting in the optical RESET phenomenon. Furthermore, by integrating with perovskite solar cells, an all-optically controlled universal implication logic gate is constructed. This work provides an important step toward the mimicry of human visual memory and the multifunctional artificial visual integration of perception and storage.