Photoemission electron microscopy of exciton-polaritons in thin WSe${}_2$ waveguides

Abstract

Exciton-polaritons emerging from the interaction of photons and excitons in the strong coupling regime are intriguing quasiparticles for the potential exchange of energy during light-matter interaction processes such as light harvesting. The coupling causes an energy anti-crossing in the photon dispersion centered around the exciton resonance, i.e., a Rabi splitting between a lower and upper energetic branch. The size of this splitting correlates with the coupling strength between the exciton and the photonic modes. In this work, we investigate this coupling between excitons and photonic waveguide modes excited simultaneously in thin-film flakes of the transition-metal dichalcogenide WSe${}_2$. Using a Photoemission electron microscope, we are able to extract the dispersion of the transversal electric and magnetic modes propagating through these flakes as well as extract the energy splitting. Ultimately, our findings provide a basis for the investigation of the propagation of exciton-polaritons in the time-domain via time-resolved photoemission.

References in corpus (11)

• Exciton Binding Energy and Nonhydrogenic Rydberg Series in Monolayer WS2
• Excitons in atomically thin transition metal dichalcogenides
• Strong light-matter coupling in two-dimensional atomic crystals
• Exciton Binding Energy of Monolayer WS2
• Exciton-polaritons in van der Waals heterostructures embedded in tunable microcavities
• Room temperature Tamm-Plasmon Exciton-Polaritons with a WSe2 monolayer
• Imaging exciton-polariton transport in MoSe2 waveguides
• Valley-Polarized Exciton-Polaritons in a Monolayer Semiconductor
• Thickness dependence of work function, ionization energy, and electron affinity of Mo and W dichalcogenides from DFT and GW calculations
• Nano-optical imaging of WSe2 waveguide modes revealing light-exciton interactions
• Energy and Momentum Distribution of Surface Plasmon-induced Hot Carriers Isolated via Spatiotemporal Separation