All-Photon Bipolar Reversible Modulation Artificial Synapse for Color Perception and Mitigation of Glare Phenomenon

The convergence of computation and storage through artificial synapses is a vibrant area of research, with notable attention directed toward photonic artificial synapses, particularly in emulating human visual perception and memory. However, many of these solutions necessitate both optical and electrical signals for bidirectional modulation. In this work, we report an optically responsive memristor (with a configuration of Ag:AgI/MA0.4FA0.6PbI3/Ag:AgI) that achieves bidirectional switching of resistive states utilizing 450 and 650 nm light at an ultralow readout voltage of 0.001 V. The maximum high-to-low resistive switching ratio can attain an impressive value of 74,459 at the readout voltage of 0.01 V, enabling comprehensive photonic bipolar modulation. The device presents artificial visual synapse (AVS) features in terms of short-term plasticity (STP)/long-term plasticity (LTP) to pulsed light in the range 300–700 nm. Under 450 nm blue light, an abrupt shift from low to high resistance can be observed, resembling the effect of glare. Intriguingly, the introduction of 650 nm red light can expedite recovery following blue light exposure. These attributes underscore the potential of the device for tasks encompassing color recognition, memory functions, and adaptation, suggesting promising prospects within artificial visual neural networks for ultraviolet and visible light sensing, transmission, and memory applications.