Exciton Localization in Two‐Dimensional Semiconductors through Modification of the Dielectric Environment

Monolayer semiconductors, given their thickness at the atomic scale, present unique electrostatic environments due to the sharp interfaces between the semiconductor film and surrounding materials. These interfaces significantly impact both the quasiparticle band structure and the electrostatic interactions between charge carriers. A key area of interest in these materials is the behavior of bound electron–hole pairs (excitons) within the ultrathin layer, which plays a crucial role in its optoelectronic properties. In this work, the feasibility of generating potential traps that completely confine excitons in the thin semiconductor by engineering the surrounding dielectric environment is investigated. By evaluating the simultaneous effects on bandgap renormalization and modifications to the strength of the electron–hole Coulomb interaction, the existence of low‐energy regions in which the localization of the exciton center of mass may be achieved is anticipated. The results suggest that for certain dielectric configurations, it is possible to generate complete discretization of exciton eigenenergies in the order of tens of meV. Such quantization of energy levels of 2D excitons can be harnessed for applications in new‐generation optoelectronic devices, which are necessary for the advancement of technologies like quantum computing and quantum communication.