Coulomb-bound four- and five-particle valleytronic states in an atomically-thin semiconductor

Abstract

As hosts for tightly-bound electron-hole pairs carrying quantized angular momentum, atomically-thin semiconductors of transition metal dichalcogenides provide an appealing platform for optically addressing the valley degree of freedom. In particular, the valleytronic properties of neutral and charged excitons in these systems have been widely investigated. Meanwhile, correlated quantum states involving more particles are so far elusive and controversial. Here we present experimental evidence for valleytronic four-particle biexcitons and five-particle exciton-trions in high-quality monolayer tungsten diselenide samples. Through charge doping, thermal activation, and magnetic-field tuning measurements, we determined that the biexciton and exciton-trion optical emissions are bound with respect to the bright exciton and the trion respectively. Further, both the biexciton and the exciton-trion are intervalley bound states involving dark excitons, giving rise to emissions with large, negative valley polarizations in contrast to that of the well-known two-particle excitons. Our studies provide new opportunities for building valleytronic quantum devices harnessing high-order excitations.

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Cited by in corpus (61)

• Revealing the Biexciton and Trion-exciton Complexes in BN Encapsulated WSe2
• Valley Phonons and Exciton Complexes in a Monolayer Semiconductor
• Electroluminescence from multi-particle exciton complexes in transition metal dichalcogenide semiconductors
• Emerging Photoluminescence from the Dark-Exciton Phonon Replica in Monolayer WSe2
• Gate tunable dark trions in monolayer WSe${}_2$
• Raman spectrum of Janus transition metal dichalcogenide monolayers WSSe and MoSSe
• Resolving spin, valley, and moiré quasi-angular momentum of interlayer excitons in WSe2/WS2 heterostructures
• Optical properties of charged excitons in two-dimensional semiconductors
• Momentum-Dark Intervalley Exciton in Monolayer Tungsten Diselenide Brightened via Chiral Phonon
• Valley-selective chiral phonon replicas of dark excitons and trions in monolayer WSe2
• Direct Observation of Gate Tunable Dark Trions in Monolayer WSe2
• Multipath optical recombination of intervalley dark excitons and trions in monolayer WSe${}_2$
• Energy spectrum of two-dimensional excitons in a non-uniform dielectric medium
• The valley Zeeman effect in inter- and intra-valley trions in monolayer WSe${}_2$
• Electron-exciton interactions in the exciton-polaron problem
• Probing and manipulating valley coherence of dark excitons in monolayer WSe${}_2$
• Probing Many-Body Interactions in Monolayer Transition-Metal Dichalcogenides
• Luminescent emission of excited Rydberg excitons from monolayer WSe2
• Exciton-polaron interactions in monolayer WS${}_2$
• Hexcitons and oxcitons in monolayer WSe${}_2$
• Excitonic complexes in $n$-doped WS${}_2$ monolayer
• Ground and Excited Exciton Polarons in Monolayer MoSe2
• Magnetooptics of layered two-dimensional semiconductors and heterostructures: progress and prospects
• Relaxation and darkening of excitonic complexes in electrostatically-doped monolayer semiconductors: Roles of exciton-electron and trion-electron interactions
• Localized Excitons in NbSe${}_2$-MoSe${}_2$ Heterostructures
• Autoionization and dressing of excited excitons by free carriers in monolayer WSe2
• Virtual trions in the photoluminescence of monolayer transition-metal dichalcogenides
• Neutral and charged dark excitons in monolayer WS${}_2$
• Few-body systems in condensed matter physics
• Enhancement of Exciton Valley Polarization in Monolayer MoS2 Induced by Scattering
• Strongly-bound excitons and trions in anisotropic 2D semiconductors
• Tuning the Optical Properties of an MoSe${}_2$ Monolayer Using Nanoscale Plasmonic Antennas
• Direct Measurement of Biexcitons in Monolayer WS2
• Up- and Down-Conversion between Intra- and Inter-Valley Excitons in Waveguide Coupled Monolayer WSe2
• Controlling valley splitting and Polarization of dark- and bi-excitons in monolayer WS${}_2$ by a tilted magnetic field
• Probing biexciton in monolayer WS${}_2$ through controlled many-body interaction
• Emergence of 6-particle "hexciton'' states in WS${}_2$ and MoSe${}_2$ monolayers
• Excited-State Trions in Two Dimensional Materials
• Charge Density Wave Activated Excitons in TiSe${}_2$-MoSe${}_2$ Heterostructures
• Tuning exciton complexes in twisted bilayer WSe2 at intermediate misorientation
• The effect of dielectric environment on the brightening of neutral and charged dark excitons in WSe${}_2$ monolayer
• Dark-state impact on the exciton recombination of WS2 monolayers as revealed by multi-time-scale pump-and-probe spectroscopy
• Trion-trion annihilation in monolayer WS${}_2$
• Effects of dynamical dielectric screening on the excitonic spectrum of monolayer semiconductors
• Excitons and trions in WSSe monolayers
• Intervalley electron-hole exchange interaction and impurity-assisted recombination of indirect excitons in WS${}_2$ and WSe${}_2$ monolayers
• Theory of the Coherent Response of Magneto-Excitons and Magneto-Biexcitons in Monolayer Transition Metal Dichalcogenides
• Charge-carrier complexes in monolayer semiconductors
• Interplay of energy and charge transfer in WSe2/CrSBr heterostructures
• Probing the bright exciton state in twisted bilayer graphene via resonant Raman scattering
• Raman scattering excitation in monolayers of semiconducting transition metal dichalcogenides
• Imaging Seebeck drift of excitons and trions in MoSe2 monolayers
• Controlling relaxation dynamics of excitonic states in monolayer transition metal dichalcogenides WS2 through interface engineering
• Hyperspectral photoluminescence and reflectance microscopy of 2D materials
• Doping-induced non-Markovian interference causes excitonic linewidth broadening in monolayer WSe${}_2$
• Multidimensional sensing of proximity magnetic fields via intrinsic activation of dark excitons in WSe${}_2$/CrCl${}_3$ heterostructure
• Energy shifts and broadening of excitonic resonances in electrostatically-doped semiconductors
• Trion confinement in monolayer MoSe2 by carbon nanotube local gating
• Extremely high excitonic $g$-factors in 2D crystals by alloy-induced admixing of band states
• Optical response of WSe${}_2$-based vertical tunneling junction
• Gate-modulated reflectance spectroscopy for detecting excitonic species in two-dimensional semiconductors