Speaker: Dr. Paulo E. de Faria Jr (University of Central Florida)

Abstract:

Van der Waals matter - systems composed of naturally occurring or artificially stacked two-dimensional layered materials - is highly sensitive to both interlayer interactions and external perturbations. The strategic stacking of distinct layered materials provides a powerful route toward emergent electronic phases and strongly interacting many-body optical excitations. In particular, transition metal dichalcogenide (TMDC) semiconductors offer a fertile playground for engineering and controlling light-matter interactions through tunable electronic and excitonic degrees of freedom. In this talk, I will discuss how external electric and magnetic fields enable tunable control of the electronic structure and excitonic properties of TMDC-based van der Waals systems. Specifically, I will present: (i) a generalized many-body theory of exciton magnetic moments applied to monolayer TMDCs [1]; (ii) the emergence of giant magnetic moments for neutral excitons in alloyed TMDCs [2]; and (iii) robust electrical control of multivalley intersubband transitions in few-layer TMDCs [3].

[1] Phys. Rev. B (Letters) 112, L241404 (2025).

[2] Phys. Rev. Lett. (Editors' Suggestion) 136, 076901 (2026).

[3] ACS Nano 20, 4018 (2026).