Anomalously Robust Valley Polarization and Valley Coherence in Bilayer WS2

Abstract

Coherence is a crucial requirement to realize quantum manipulation through light-matter interactions. Here we report the observation of anomalously robust valley polarization and valley coherence in bilayer WS2. The polarization of the photoluminescence from bilayer WS2 inherits that of the excitation source with both circularly and linearly polarized and retains even at room temperature. The near unity circular polarization of the luminescence reveals the coupling of spin, layer and valley degree of freedom in bilayer system, while the linear polarized photoluminescence manifests quantum coherence between the two inequivalent band extrema in momentum space, namely, the valley quantum coherence in atomically thin bilayer WS2. This observation opens new perspectives for quantum manipulation in atomically thin semiconductors.

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Cited by in corpus (75)

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• Nanoscale chiral valley-photon interface through optical spin-orbit coupling
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• Interlayer coupling in commensurate and incommensurate bilayer structures of transition metal dichalcogenides
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• Polarization and time-resolved photoluminescence spectroscopy of excitons in MoSe2 monolayers
• A- and B-Exciton Photoluminescence Intensity Ratio as a Measure of Sample Quality for Transition Metal Dichalcogenide Monolayers
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• Direct exciton emission from atomically thin transition metal dichalcogenide heterostructures near the lifetime limit
• The Effect of Preparation Conditions on Raman and Photoluminescence of Monolayer WS2
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• Enhanced Optoelectronic Response in Bilayer Lateral Heterostructures of Transition Metal Dichalcogenides
• Diffusion quantum Monte Carlo study of excitonic complexes in two-dimensional transition-metal dichalcogenides
• Binding energies of trions and biexcitons in two-dimensional semiconductors from diffusion quantum Monte Carlo calculations
• Binding energies and spatial structures of small carrier complexes in monolayer transition metal dichalcogenides via diffusion Monte Carlo
• Valley coherent exciton-polaritons in a monolayer semiconductor
• Routing of valley photons in a WS2 monolayer via delocalized Bloch modes of in-plane inversion-symmetry broken photonic crystal slabs
• Zeeman splitting via spin-valley-layer coupling in bilayer MoTe2
• Splitting of the monolayer out-of-plane A'1 Raman mode in few-layer WS2
• Exciton states in monolayer MoSe2: impact on interband transitions
• Line and Point Defects in MoSe2 Bilayer Studied by Scanning Tunneling Microscopy and Spectroscopy
• Manipulating Spin-polarized Photocurrent in 2D Transition Metal Dichalcogenides
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• Double resonant Raman scattering and valley coherence generation in monolayer WSe2
• Understanding Variations in Circularly Polarized Photoluminescence in Monolayer Transition Metal Dichalcogenides
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• Opto-valleytronic imaging of atomically thin semiconductors
• Intrinsic circular polarization in centrosymmetric stacks of transition-metal dichalcogenides
• Valley Trion Dynamics in Monolayer MoSe${}_2$
• Exciton dynamics in WSe2 bilayers
• Layer engineered interlayer excitons
• Observation of forbidden phonons and dark excitons by resonance Raman scattering in few-layer WS${}_2$
• Room Temperature Valley Polarization and Coherence in Transition Metal Dichalcogenide-Graphene van der Waals Heterostructures
• Magnetooptics of layered two-dimensional semiconductors and heterostructures: progress and prospects
• Novel valley depolarization dynamics and valley Hall effect of exciton in mono- and bilayer MoS${}_2$
• Trion and Biexciton in Monolayer Transition Metal Dichalcogenides
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• Scalable synthesis of WS2 on graphene and h-BN: an all-2D platform for light-matter transduction
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• Optical Valley Hall Effect based on Transitional Metal Dichalcogenide cavity polaritons
• Few-body systems in condensed matter physics
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• Prolonging Valley Polarization Lifetime through Gate-Controlled Exciton-to-Trion Conversion in Monolayer Molybdenum Ditelluride
• Near Unity Optical Spin Polarization in GaSe Nanoslabs
• Valley Degree of Freedom in Two-Dimensional van der Waals Materials
• Optical Spin Polarization Dynamics in GaSe Nanoslabs
• Spin accumulation and dynamics in inversion-symmetric van der Waals crystals
• Observation of ~100% valley-coherent excitons in monolayer MoS2 through giant enhancement of valley coherence time
• Charged exctions in two-dimensional transition-metal dichalcogenides - semiclassical calculation of Berry-curvature effects
• Magnetic field induced splitting and polarization of monolayer-based valley exciton-polaritons
• Excitonic Complexes and Emerging Interlayer Electron-Phonon Coupling in BN Encapsulated Monolayer Semiconductor Alloy: WS0.6Se1.4
• Photoluminescence Saturation and Exciton Decay Dynamics in Transition Metal Dichalcogenide Monolayers
• Impact of indirect transitions on valley polarization in WS${}_2$ and WSe${}_2$
• Interlayer Exciton Valleytronics in Bilayer Heterostructures Interfaced with a Metasurface
• Excited-State Trions in Two Dimensional Materials
• Twisted MoSe2 Homobilayer Behaving as a Heterobilayer
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• Photonics in Flatland: Challenges and Opportunities for Nanophotonics with 2D Semiconductors
• Magnetic parity violation and parity-time-reversal-symmetric magnets
• Self-Induced Valley Bosonic Stimulation of Exciton-Polaritons in a Monolayer Semiconductor
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• Electrical control of orbital and vibrational interlayer coupling in bi- and trilayer 2H-MoS${}_2$
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• Morphology-induced spectral modification of self-assembled WS2 pyramids
• Phonon-mediated exciton capture in Mo-based transition metal dichalcogenides
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