Date: 19.01.2023, Time: 15:30h

Location: Adolf-von-Baeyer-Hörsaal, Butenandtstr. 5-13
The talk will also be streamed online.

Prof. Ermin Malic
Ultrafast Quantum Dynamics Group - Department of Physics, Philipps-Universität Marburg

Monolayer transition metal dichalcogenides (TMDs) and related van der Waals heterostructures exhibit a rich
exciton physics including bright and a variety of dark states as well as spatially separated interlayer and hybrid
exciton states. Solving 2D material Bloch equations for excitons, phonons and photons, we obtain a
microscopic access to the interplay of optics, dynamics and transport of excitons in these technologically
promising materials.
In joint theory-experiment studies, we shed light in particular on the importance of interlayer and hybrid exciton
states for the twist-angle dependent optical fingerprint revealed in low-temperature photoluminescence spectra
[1,2], the ultrafast phonon-driven charge transfer dynamics visualized by tr-ARPES measurements [3,4], and
the field- and strain-driven transport behavior [5,6] shown in spatiotemporal photoluminescence spectra.
The gained microscopic insights into the spatiotemporal exciton dynamics are crucial for understanding and
controlling many-particle phenomena governing exciton optics, dynamics and transport in technologically
promising 2D materials and related heterostructures.

[1] J. Hagel, S. Brem, E. Malic, Electrical tuning of moiré excitons in MoSe2 bilayers, 2D Mat. 10, 14013 (2023)
[2] S. Brem, E. Malic, Bosonic Delocalization of Dipolar Moiré Excitons, Nano Letters 23. 4627 (2023)
[3] D. Schmitt, … E. Malic, S. Hofmann, M. Reutzel and S. Mathias, Formation of moiré interlayer excitons in
space and time, Nature 608, 499 (2022)
[4] Meneghini, S. Brem, E. Malic, Natural Sciences, e20220014 (2022)
[5] F. Tagarelli, … E. Malic, A. Kis, Electrical control of hybrid exciton transport in a van der Waals
heterostructure, Nature Photonics 17, 615 (2023)
[6] R. Rosati, … R. Bratschitsch, E. Malic, Dark exciton antifunneling in atomically thin semiconductors,
Nature Communications 12, 7221 (2021)