Optoelectronic memory in 2D MoS2 field effect transistor

2D layered materials with their tunable bandgap and unique crystal structures are excellent candidates for 2D optoelectronic memories. In this work, we present a simple approach for the realization of a nonvolatile optoelectronic memory device based on a MoS2 transistor with light induced charge storage capability. The MoS2 transistor shows 108 on/off current ratio and hysteresis width modulation by air pressure under normal and quiet measurement conditions. Moreover, the device shows persistent photoconductivity and exhibits excellent photo responsive memory performance with a current switching ratio of two orders of magnitude and a photocurrent that increases linearly with the incident light power. We show that a combination of gate voltage and light can be used to control the transistor current and increase the memory window by two orders of magnitude. The obtained results are a significant step toward the improvement of optoelectronic devices, showing that the combination of gate voltage and light can enable a multilevel memory device.