Michele Re Fiorentin I Excitonic properties of new 2D materials and van der Waals heterostructures

Michele Re Fiorentin
Dipartimento Scienza Applicata e Tecnologia (DISAT), Politecnico di Torino, Torino (Italy)

Two-dimensional (2D) materials have gained significant attention due to their unique electronic and optical properties. In this presentation, I will discuss two recent studies that explore the use of 2D materials for optoelectronic applications. The first study investigated the electronic and optical properties of novel semiconducting materials with chemical formula MoSi2X4 (X = N, P, As) using state-of-the-art ab initio many-body perturbation theory. The results showed promising long radiative lifetimes of bright excitons and the absence of band-nesting, which could enable efficient ultra-thin optoelectronic devices. In the second study, a new vertical heterostructure of less-common transition-metal dichalcogenides (TMDs) 1T-PdS2/PtS2 was explored for use in ultrathin photovoltaic applications. The computed excitonic landscape predicted outstanding light absorbance, partial charge separation between the layers, and increased carrier diffusion length. These examples demonstrate how theoretical simulations can be used to explore the properties of 2D materials and their applications in optoelectronic devices.