Emerging Photoluminescence from the Dark-Exciton Phonon Replica in Monolayer WSe2

Abstract

Tungsten-based monolayer transition metal dichalcogenides host a long-lived dark exciton, an electron-hole pair in a spin-triplet configuration. The long lifetime and unique spin properties of the dark exciton provide exciting opportunities to explore light-matter interactions beyond electric dipole transitions. Here we demonstrate that the coupling of the dark exciton and an optically silent chiral phonon enables the intrinsic photoluminescence of the dark-exciton replica in monolayer WSe2. Gate and magnetic-field dependent PL measurements unveil a circularly-polarized replica peak located below the dark exciton by 21.6 meV, equal to E" phonon energy from Se vibrations. First-principles calculations show that the exciton-phonon interaction selectively couples the spin-forbidden dark exciton to the intravalley spin-allowed bright exciton, permitting the simultaneous emission of a chiral phonon and a circularly-polarized photon. Our discovery and understanding of the phonon replica reveals a chirality dictated emission channel of the phonons and photons, unveiling a new route of manipulating valley-spin.

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Cited by in corpus (45)

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• Multipath optical recombination of intervalley dark excitons and trions in monolayer WSe${}_2$
• Phonon Magnetic Moment from Electronic Topological Magnetization
• Exciton optics, dynamics and transport in atomically thin semiconductors
• Probing dark exciton navigation through a local strain landscape in a WSe${}_2$ monolayer
• Nonclassical Exciton Diffusion in Monolayer WSe2
• Exciton-phonon coupling strength in single-layer MoSe2 at room temperature
• Excitonic complexes in $n$-doped WS${}_2$ monolayer
• Magnetooptics of layered two-dimensional semiconductors and heterostructures: progress and prospects
• High Density, Localized Quantum Emitters in Strained 2D Semiconductors
• Rydberg series of dark excitons and the conduction band spin-orbit splitting in monolayer WSe${}_2$
• Landau-quantized excitonic absorption and luminescence in a monolayer valley semiconductor
• Neutral and charged dark excitons in monolayer WS${}_2$
• Temporal evolution of low-temperature phonon sidebands in WSe${}_2$ monolayers
• Gate-tunable phonon magnetic moment in bilayer graphene
• Spatially indirect intervalley excitons in bilayer WSe2
• Chiral valley phonons and flat phonon bands in moiré materials
• Manipulation of Exciton Dynamics in Single-Layer WSe2 Using a Toroidal Dielectric Metasurface
• Ab initio self-trapped excitons
• Visualization of dark excitons in semiconductor monolayers for high-sensitivity strain sensing
• Luminescence anomaly of dipolar valley excitons in homobilayer semiconductor moiré superlattices
• Valley-Filling Instability and Critical Magnetic Field for Interaction-Enhanced Zeeman Response in Doped WSe${}_2$ Monolayers
• Phonon chirality manipulation mechanism in TMD interlayer-sliding ferroelectrics
• Charge Density Wave Activated Excitons in TiSe${}_2$-MoSe${}_2$ Heterostructures
• Tuning exciton complexes in twisted bilayer WSe2 at intermediate misorientation
• Exciton-activated effective phonon magnetic moment in monolayer MoS2
• 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
• Electrically Controlled Interfacial Charge Transfer Induced Excitons in MoSe2-WSe2 Lateral Heterostructure
• Interplay of valley polarized dark trion and dark exciton-polaron in monolayer WSe2
• Ab initio calculations of spin-nonconserving exciton-phonon scattering in monolayer transition metal dichalcogenides
• Local photodoping in monolayer MoS2
• Raman scattering excitation in monolayers of semiconducting transition metal dichalcogenides
• Chiral phonons in binary compounds $A$Bi ($A$ = K, Rb, Cs) with P2${}_1$/c structure
• Magneto-Optical Measurements of the Negatively Charged 2$s$ Exciton in WSe${}_2$
• Physics of Phonons in Systems with Approximate Screw Symmetry
• Multidimensional sensing of proximity magnetic fields via intrinsic activation of dark excitons in WSe${}_2$/CrCl${}_3$ heterostructure
• Single charge control of localized excitons in heterostructures with ferroelectric thin films and two-dimensional transition metal dichalcogenides
• Chiral phonons of honeycomb-type bilayer Wigner crystals
• Extremely high excitonic $g$-factors in 2D crystals by alloy-induced admixing of band states
• Optical response of WSe${}_2$-based vertical tunneling junction
• Electrically modulated light-emitting diodes driven by resonant and antiresonant tunneling between Cr${}_2$Ge${}_2$Te${}_6$ electrodes
• Moire-Engineered Excitonic Landscape and Phonon-Mediated Recombination in Twisted WSe2 Bilayers