2D Materials – Physics of
van der Waals [hetero]structures

Atomistic theory of excited states in van-der-Waals heterostructures: Moiré confinement, strain and electric field effects

Principal investigator

Gabriel Bester, Universität Hamburg [webpage]

Abstract

The aim of this theoretical project is to provide an accurate and predictive atomistic description of the excited states in van-der-Waals heterostructures including moiré confinement effects (left figure). More specifically, we aim at a detailed understanding of the often complex optical signatures of excitons, biexcitons and trions in twisted homo- and hetero-bilayers of TMDs. We will work in collaboration with experimental groups of the consortium and study the effects of strain and electric fields on the excited states properties.

Our methodology (right figure) is atomistic, including up to 3,000 atoms at the DFT level and up to 50,000 atoms at the AEP level (semi-empirical). The structural relaxation is performed using our force field. The single-particle results are subsequently used in our screened CI methodology to obtain excitons, trions and biexcitons.