Laser-Engineered Artificial Edges of 2D MoS ₂ Enabling Active Sites for Localized Exciton-Trion Modulations

Artificial edge engineering in two-dimensional transition metal dichalcogenides (TMDCs) offers a direct means to manipulate their excitonic landscape. Motivated by this, we employ laser-induced nanopatterning to create controlled artificial edges in few-layer MoS 2 and probe their impact on local electronic and optical properties using micro-photoluminescence. Edge regions exhibit markedly enhanced trion emission and distinct excitonic peak shifts compared to the far edge region, signatures of elevated free carrier density arising from defect-induced electronic structure modifications. The observed interplay between excitons and excess carriers underscores the role of edge states as preferential charge accumulation sites, also observed in Electrostatic Force Microscopy (EFM) phase imaging. This suggests that edge engineering plays a crucial role in tuning the charge carrier concentration and, consequently, the optical properties of MoS 2, providing a pathway toward the development of tunable optoelectronic properties.