Exciton Modulation Through Laser Elucidation in Two Dimensional MoS₂

Modification of two-dimensional transition metal dichalcogenide enables a wide variety of electric and optical applications; however, this often results in introduction of undesirable properties. Current methods for defect modification include the use of chemical doping and ion bombardment. One possible solution lies in the use of laser radiation for controlled and precise property alteration. As prepared 2D MoS2 is initially p-doped with laser irradiation while continued elucidation results in photocleaning. Changes are best characterized using the photoluminescent behavior - specifically the A and B exciton – in additional to E2g and A1g Raman peaks. To determine the extent that MoS₂ is modified, we analyzed the spectra of Confocal Raman, photoluminescence, and determined carrier concentration using the Mass Action model and experimentally confirmed with Kelvin Probe Force Microscopy. The critical point where doping begins to lead to a reduction in sample quality is further analyzed.