Optoelectronic Synaptic Memristor with Coupled Reversible Self‐Rectifying and Bipolar Resistive Switching for Multifunctional Neuromorphic Applications

Abstract Self‐rectifying optoelectronic synaptic memristor integrates the multi‐field regulated dynamic plasticity of biological synapses while effectively addressing the long‐standing challenge of parasitic current suppression in high‐density device arrays. This work demonstrates an Ag/CZTSSe/Mo (CZTSSe: Cu 2 ZnSn(S, Se) 4 ) optoelectronic synaptic memristor enabling reversible switching between bipolar resistive switching and self‐rectifying modes, thus functioning simultaneously as a selector and memristor. The non‐volatile bipolar switching behavior features bias‐modulated On/Off ratio (2.2 × 10 2 –5.1 × 10 3 ) and a near‐infrared light‐tunable reset voltage (0.52–0.06 V), while the self‐rectifying characteristic maintains a rectification ratio of >10 3 over 100 switching cycles. Under either electrical or light (470–980 nm) stimuli, the memristor emulates key artificial synaptic behaviors, including excitatory postsynaptic current, paired‐pulse facilitation, long‐term potentiation/depression, spike‐timing‐dependent plasticity, and short‐to‐long‐term memory (S/LTM) transitions. Notably, its realized applications, including 1) reset‐dominated unclonable security encryption, 2) visible‐light vision imaging to near‐infrared weak‐signal detection, and 3) envelope demodulation of amplitude‐modulated signals for long‐distance high‐accuracy data transmission, highlight its cross‐disciplinary advantages in neuromorphic computing.