Engineering exciton emission in monolayer TMDCs by dielectric encapsulation

Monolayer TMDCs are direct band gap semiconductors having exciton emission in the visible spectrum. Exciton emission engineering in monolayer TMDCs is highly relevant for application in optoelectronics and valleytronics. Chemical vapour deposition and mechanical exfoliation are two established ways of obtaining monolayer TMDCs. In this work, we present the engineering of photoluminescence of MoS₂ by dielectric encapsulation. It has been reported that the encapsulation of 2D material can improve the exciton emission properties, such as the linewidths, stability and saturation intensity. We investigate and compare the excitonic features of MoS₂ encapsulated by van der waal dielectric versus non van der waal dielectric at low as well as room temperature. Gate voltage and excitation power dependent measurements further validate our findings.