Reversible Transition of Volatile and Nonvolatile Switching in Ag–In–Zn–S Quantum Dot-Based Memristors with Low Power Consumption for Synaptic Applications

Neuromorphic computing systems composed of electronic synapses and neurons provide an effective choice to construct the next generation of intelligent computing systems. However, poor resistive switching uniformity and high power consumption of the reported electronic synapses are the major obstacles for developing large-scale brain-inspired computing systems. Herein, quaternary Ag–In–Zn–S (AIZS) quantum dots (QDs) have been utilized to fabricate a kind of electronic synaptic devices with crossbar-array structure. The devices exhibit excellent electrical performance, including uniformly distributed operation voltages, reliable data retention, robust cycle measurement, and large memory window. More interestingly, the devices can achieve reversible transitions between volatile switching and nonvolatile memory switching in a single QD-based cell by modulating the compliance current. The power consumption per switching can be achieved as low as ∼10 pW. Additionally, the Schottky emission and ohmic conduction can be used to account for the switching mechanisms well. Furthermore, biological synaptic-like behaviors have been successfully mimicked by QD-based devices, including short-term potentiation, paired-pulse facilitation, long-term potentiation/depression, and the preliminary transition from short-term memory to long-term memory. These results reveal that the QD-based device with excellent performance might be a potential candidate for energy-efficient brain-inspired computing applications.