Abstract of the talk// Excitons in two-dimensional materials are highly sensitive to structural perturbations, offering opportunities to control and fine-tune their behavior through often reversible mechanisms. In this talk, Amir will present his findings on how different types of structural modifications influence excitonic properties and induce exciton dynamics in transition-metal dichalcogenides (TMD). Using many-body perturbation theory, I examine how the optical response of TMD–graphene heterostructures is affected by interlayer twist and chalcogen vacancies. These perturbations modify the degree of hybridization and localization, leading to distinct changes in exciton character and optical spectra.

Amir will then turn to spatially inhomogeneous strain, exploring its role in driving exciton dynamics. Starting from ab initio strain-dependent band structures, he derives excitonic potentials that vary with both position and momentum. Exciton distributions are then evolved on these landscapes, revealing how realistic strain profiles can guide, focus, or suppress exciton flow. Together, these studies show how structural perturbations, from atomic defects to large-scale strain, can profoundly affect both the nature and motion of excitons in 2D materials, and how first-principles methods can be used to predict and understand these effects.