Multibit MoS₂Photoelectronic Memory with Ultrahigh Sensitivity

The operation of a generic single-layer MoS₂ photoelectronic memory device that fully utilized the exotic electrical and optical properties of single-layer MoS₂. A single-layer MoS₂ flake with a direct band gap of 1.8 eV acted as both a channel material and a light-absorption layer, and AuNPs were employed as the charge-trapping layers to achieve high-performance memory operation. Photoillumination excited the electrons in the MoS₂ layer valence band into the conduction band. Before the photoinduced excitons had recombined, the application of a negative gate voltage induced charge transfer from the AuNPs to the MoS₂ valance band. The transferred electrons prohibited recombination among the photoexcited electrons, which enabled the persistent storage of photonic signals. The transferred electrons prohibited recombination among the photoexcited electrons, which enabled the persistent storage of photonic signals. The multilevel data storage could be deterministically reconfigured by both the applied gate voltage and the illumination power. The resulting MoS₂ photoelectronic memories exhibited excellent memory characteristics, including a large programming/erasing current ratio, multilevel data storage, cyclic endurance, and stable retention.