Excitons in TMDs from many-body perturbation theory

Abstract

Electron-hole excitations, or excitons, play a key role in energy conversion processes and photophysics applications. The exciton transport and decay properties are strongly coupled to structural complexities. They are of particular interest upon layered heterostructures of transition metal dichalcogenides (TMDs), a structural composition that introduces non-trivial interlayer excitonic effects. In this talk, I will describe a computational approach to study the excitonic phenomena at TMD heterostructures, using ab initio many-body perturbation theory. I will discuss many-body effects on optical selection rules and exciton phenomena in and between layered transition metal dichalcogenides, where a mixed nature of electron-hole interactions control the optical transitions and the exciton fine structure. I will further present a new approach to study exciton decay processes upon such junctions from first principles.