Regensburg 2025 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
HL: Fachverband Halbleiterphysik
HL 11: Ultra-fast Phenomena I
HL 11.7: Talk
Monday, March 17, 2025, 17:45–18:00, H14
Ultrafast Coherent Dynamics of a Hybrid WS2/Plasmon Structure Probed by Two-Dimensional Electronic Spectroscopy — •Daniel Timmer1, Moritz Gittinger1, Daniel C. Lünemann1, Thomas Quenzel1, Sven Stephan1,2, Martin Silies1,2, Antonietta De Sio1, and Christoph Lienau1 — 1IfP, Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany — 2ILO, Hochschule Emden/Leer, Emden, Germany
Transition metal dichalcogenide (TMD) monolayers (1L) have been established as important building blocks for quantum materials. Hybridization between light and matter states, in particular in plasmonic nanostructures, offers great opportunities to tailor their optical and electronic properties [1]. Here, we investigate such a hybrid plasmonic structure in the intermediate coupling regime comprised of 1L-WS2 [2] placed on a periodic silver nano-slit array using ultrafast two-dimensional electronic spectroscopy (2DES). We observe a 20-fold increase of the optical nonlinearity and ultrafast coherent plexciton dynamics during the dephasing time (~50 fs). We rationalize our observations via a Tavis-Cummings model that gives rise to collective dark states and a Rabi contraction of the 2-quantum states. Using ultrafast 2DES, we obtain access to probe and disentangle the coherent and incoherent dynamics in TMD-based plasmonic systems. [1]: Timmer et al. "Plasmon mediated coherent population oscillations in molecular aggregates." Nat. Commun. 14.1 (2023): 8035. [2]: Timmer et al. "Ultrafast Coherent Exciton Couplings and Many-Body Interactions in Monolayer WS2" Nano Lett. 24.26 (2024): 8117-8125.
Keywords: Ultrafast two-dimensional electronic spectroscopy; Rabi oscillations; Exciton polaritons; Transition metal dichalcogenides; Tavis-Cummings model