Manipulation of exciton and trion quasiparticles in monolayer WS2 via charge transfer

Understand

Charge doping in transition metal dichalcogenide is currently a subject of high importance for future electronic and optoelectronic applications.

• Here we demonstrate chemical doping in CVD grown monolayer (1L) of WS2 by a few commonly used laboratory solvents by investigating the room temperature photoluminescence (PL).
• The appearance of distinct trionic emission in the PL spectra and quenched PL intensities suggest n-type doping in WS2.
• The temperature-dependent PL spectra of the doped 1L-WS2 reveal significant enhancement of trion emission intensity over the excitonic emission at low temperature indicating the stability of trion at low temperature.