Observation of exciton redshift-blueshift crossover in monolayer WS2

Abstract

We report a rare atom-like interaction between excitons in monolayer WS2, measured using ultrafast absorption spectroscopy. At increasing excitation density, the exciton resonance energy exhibits a pronounced redshift followed by an anomalous blueshift. Using both material-realistic computation and phenomenological modeling, we attribute this observation to plasma effects and an attraction-repulsion crossover of the exciton-exciton interaction that mimics the Lennard-Jones potential between atoms. Our experiment demonstrates a strong analogy between excitons and atoms with respect to inter-particle interaction, which holds promise to pursue the predicted liquid and crystalline phases of excitons in two-dimensional materials.

References in corpus (19)

• Atomically thin MoS2: A new direct-gap semiconductor
• Synthesis of Large-Area MoS2 Atomic Layers with Chemical Vapor Deposition
• Observation of tightly bound trions in monolayer MoS2
• Exciton Binding Energy and Nonhydrogenic Rydberg Series in Monolayer WS2
• Observation of giant bandgap renormalization and excitonic effects in a monolayer transition metal dichalcogenide semiconductor
• Extraordinary room-temperature photoluminescence in WS2 monolayers
• Electrical Control of Two-Dimensional Neutral and Charged Excitons in a Monolayer Semiconductor
• Measurement of the optical dielectric function of transition metal dichalcogenide monolayers: MoS2, MoSe2, WS2 and WSe2
• Theory of Neutral and Charged Excitons in Monolayer Transition Metal Dichalcogenides
• Probing excitonic states in ultraclean suspended two-dimensional semiconductors by photocurrent spectroscopy
• Photo-Induced Bandgap Renormalization Governs the Ultrafast Response of Single-Layer MoS2
• Exciton Diamagnetic Shifts and Valley Zeeman Effects in Monolayer WS${}_2$ and MoS${}_2$ to 65 Tesla
• Trion induced negative photoconductivity in monolayer MoS2
• Intervalley biexcitons and many-body effects in monolayer MoS2
• Analysis of the exciton-exciton interaction in semiconductor quantum wells
• Fundamental Limits of Exciton-Exciton Annihilation for Light Emission in Transition Metal Dichalcogenide Monolayers
• Wannier Function Approach to Realistic Coulomb Interactions in Layered Materials and Heterostructures
• Crystallization of an exciton superfluid
• Dynamical T-matrix theory for high-density excitons in coupled quantum wells

Cited by in corpus (34)

• The dielectric impact of layer distances on exciton and trion binding energies in van der Waals heterostructures
• Exciton-exciton interaction in transition metal dichalcogenide monolayers and van der Waals heterostructures
• Mechanisms of Ultrafast Charge Separation in a PTB7/Monolayer MoS2 van der Waals Heterojunction
• Excitation-induced transition to indirect band gaps in atomically thin transition metal dichalcogenide semiconductors
• Exciton Mott transition revisited
• Bandgap Control in Two-Dimensional Semiconductors via Coherent Doping of Plasmonic Hot Electrons
• Interfacial bound exciton state in a hybrid structure of monolayer WS2 and InGaN quantum dots
• Broadband pump-probe study of biexcitons in chemically exfoliated layered WS${}_2$
• Interaction-driven transport of dark excitons in 2D semiconductors with phonon-mediated optical readout
• Frequency-dependent substrate screening of excitons in atomically thin transition metal dichalcogenide semiconductors
• Hot carrier extraction from 2D semiconductor photoelectrodes
• Van der Waals heterostructure metasurfaces: atomic-layer assembly of ultrathin optical cavities
• Phonon-assisted electronic states modulation of few-layer PdSe2 at terahertz frequencies
• Phonon-assisted processes in the ultraviolet transient optical response of graphene
• Photophysical comparison of liquid and mechanically exfoliated WS${}_2$ monolayers
• Incoherent phonon population and exciton-exciton annihilation in monolayer WS2 revealed by time-resolved spontaneous Raman scattering
• Ultrafast charge carrier and exciton dynamics in an excitonic insulator probed by time-resolved photoemission spectroscopy
• Observation of Dynamic Screening in the Excited Exciton States in Multi-layered MoS${}_2$
• Quantum interference between the optical Stark effect and resonant harmonic generation in WS2
• Exciton-exciton Interaction in Monolayer MoSe${}_2$ from Mutual Screening of Coulomb Binding
• Trion formation resolves observed peak shifts in the optical spectra of transition metal dichalcogenides
• Effect of photoinduced screening on the spectroscopic signature of exciton-phonon coupling
• Imaging Seebeck drift of excitons and trions in MoSe2 monolayers
• Dynamic screening of quasiparticles in WS${}_2$ monolayers
• Kohn-Sham-Proca equations for ultrafast exciton dynamics
• Dipolar polaritons squeezed at unitarity
• Guiding light with surface exciton-polaritons in atomically thin superlattices
• Ultrafast melting of charge-density wave fluctuations at room temperature in $1T-TiS{e}_2$ monitored under non-equilibrium conditions
• Exciton Mott Transition in Two-Dimensional Semiconductors
• Exciton energy oscillations induced by quantum beats
• Direct observation of ultrafast defect-bound and free exciton dynamics in defect-engineered WS${}_2$ monolayers
• Long-lived populations of momentum- and spin-indirect excitons in monolayer WSe${}_2$
• Tracking the photoinduced dynamics of a dark excitonic state in single-layer WS${}_2$ via resonant Autler-Townes splitting
• Ultrafast Insight into High energy (C, D) Excitons in Few Layer WS2