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

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.