The JCMS series

The Joint Condensed Matter Seminar (JCMS) series is organised by KTH Royal Insitute of Technology, Nordita, and Stockholm University.

May 8th, 2025: Giuseppe Meneghini

On Thursday, May 8th, 2025 from 13.30 am to 14.30 we will host a seminar by Giuseppe Meneghini from University of Marburg.

Title

Hybrid Exciton Thermalization in van der Waals Heterostructures

Abstract

Transition metal dichalcogenides (TMDs) exhibit enhanced light-matter and Coulomb interactions, giving rise to a rich landscape of tightly bound excitons. Stacking TMD monolayers into van der Waals heterostructures further enriches this scenario, introducing spatially separated interlayer excitons characterized by long lifetimes and a permanent out-of-plane dipole moment. Recent experiments have revealed fascinating phenomena associated with interlayer exciton formation, including ultrafast charge transfer between layers and long-lived excited states whose photoluminescence brightness depends sensitively on the twist angle. Based on a microscopic, material-realistic exciton theory, we investigate the dynamics of layer- and momentum-hybridized excitons in bilayer systems. In this talk, I will present the basic concepts of the microscopic model and illustrate how our results have helped to interpret and understand the experimental observations.