Gate-Tunable Photomemory Effect in MoS₂ Transistors

We report a photomemory effect with the record of on/off ratio and retention time in MoS₂ transistors. The photomemory is controlled by gate voltage application, exhibiting multilevel states. Further, a memory state is recorded mainly on the laser spot area, demonstrating strong potential for photomemory miniaturization. The photomemory effect presented here is based on a photodoping effect. In such a way, the combined actions of laser exposure and application of gate potentials set large densities of charges in MoS₂ channel. Such outstanding modification of MoS₂ conductance allows definition of the binary memory states. In this way, our work opens possibilities for novel memory architectures.