Perovskite Nanocrystal/InGaZnO Heterojunction Enabling an All-Optically Controlled Artificial Synapse for Motion Detection

Optoelectronic synapses that integrate light sensing and processing functions have attracted significant interest for their potential to develop neuromorphic vision systems. In particular, an all-optically modulated device is highly desired for high-efficiency image information processing. Here, an optoelectronic synapse with all-optical modulation based on perovskite nanocrystal and InGaZnO (IGZO) heterojunctions is demonstrated. Excitatory and inhibitory synaptic plasticity can be obtained under 320 and 532 nm irradiation, which stem from the ionization and deionization process of oxygen vacancies in IGZO. Moreover, five basic optoelectronic logic operations are implemented in the optoelectronic synapse via fully light-controlled methods. By utilizing the frame difference algorithm, the function of motion detection is demonstrated for recognizing classic moving vehicles with an accuracy exceeding 90%. This work provides a promising approach to developing all-optically modulated artificial synapses and shows great potential in neuromorphic vision systems.