Revealing the Potential of Perovskite Transistors for Dual-Modulated Synaptic Behavior through Heterojunction Design

Recently, metal halide perovskites for neuromorphic information processing have emerged due to their attractive optoelectronic properties such as high photosensitivity and good charge transport. However, perovskites used as active channels in synaptic transistors have rarely been discussed due to the difficulty in controlling the charge-transporting properties. In this study, we realized electrically/optically modulated synaptic plasticity through a heterojunction design consisting of PEA2SnI4 and C60. By inserting an ultrathin polyethylenimine ethoxylated (PEIE) layer into the heterostructure, the PEA2SnI4 film quality is greatly improved and shows efficient charge-transporting behavior. In electrical modulation, synaptic potentiation and depression are simultaneously achieved by gate voltage modulation. In optical modulation, synaptic plasticity is realized under green light (530 nm) irradiation. Such dual-modulation charge-storage behavior is realized for the first time in perovskite transistors, revealing great potential for future neuromorphic intelligent applications.