Dynamic screening of quasiparticles in WS${}_2$ monolayers

Abstract

We unravel the influence of quasiparticle screening in the non-equilibrium exciton dynamics of monolayer WS${}_2$. We report pump photon energy-dependent exciton blue and red-shifts from time-resolved-reflectance contrast measurements. Based on a phenomenological model, we isolate the effective impact of excitons and free carriers on the renormalization of the quasi-free particle band gap, exciton binding energy and linewidth broadening. By this, our work does not only provide a comprehensive picture of the competing phenomena governing the exciton dynamics in WS${}_2$ upon photoexcitation, but also demonstrates that exciton and carrier contributions to dynamic screening of the Coulomb interaction differ significantly.

References in corpus (20)

• Emerging Device Applications for Semiconducting Two-Dimensional Transition Metal Dichalcogenides
• Excitons in atomically thin transition metal dichalcogenides
• Exciton Binding Energy of Monolayer WS2
• Valley-selective optical Stark effect in monolayer WS2
• Intrinsic Exciton Linewidth in Monolayer Transition Metal Dichalcogenides
• Excitonic linewidth and coherence lifetime in monolayer transition metal dichalcogenides
• Origin of indirect optical transitions in few-layer MoS2, WS2 and WSe2
• Photo-Induced Bandgap Renormalization Governs the Ultrafast Response of Single-Layer MoS2
• Exciton Dynamics in Monolayer Transition Metal Dichalcogenides
• Excitons versus electron-hole plasma in monolayer transition metal dichalcogenide semiconductors
• Fundamental Limits of Exciton-Exciton Annihilation for Light Emission in Transition Metal Dichalcogenide Monolayers
• Observation of exciton redshift-blueshift crossover in monolayer WS2
• Direct Determination of Band Gap Renormalization in Photo-Excited Monolayer MoS2
• The ultrafast onset of exciton formation in 2D semiconductors
• Fast Exciton Annihilation by Capture of Electrons or Holes by Defects via Auger Scattering in Monolayer Metal Dichalcogenides
• Ultrafast dynamics in monolayer TMDCs: the interplay of dark excitons, phonons and intervalley Coulomb exchange
• Nonequilibrium Lattice Dynamics in Monolayer MoS2
• Layer-Resolved Absorption of Light in Arbitrarily Anisotropic Heterostructures
• Exciton-Driven Renormalization of Quasiparticle Band Structure in Monolayer MoS2
• Incoherent phonon population and exciton-exciton annihilation in monolayer WS2 revealed by time-resolved spontaneous Raman scattering

Cited by in corpus (2)

• Momentum-Resolved Signatures of Carrier Screening Effects on Electron-Phonon Coupling in MoS${}_2$
• Effect of photoinduced screening on the spectroscopic signature of exciton-phonon coupling