Valley-spin polarized Landau levels in a monolayer semiconductor

Abstract

Electrons in monolayer transition metal dichalcogenides (TMDs) possess both the valley and spin degree of freedom. These internal quantum degrees of freedom have provided an ideal laboratory for exploring both new physical phenomena and electronics and photonics applications. Valley- and spin-dependent optical and electrical properties, originated from Berry curvature effects, have been recently demonstrated. Such Berry curvature effects, together with strong spin-orbit interactions, can further generate unconventional Landau levels (LLs) under a perpendicular magnetic field that support valley- and spinpolarized chiral edge states in the quantum Hall regime. The unique LL structure, however, has not been demonstrated in TMDs. Here we report the observation of fully valley- and spin-polarized LLs in high-quality WSe2 monolayers achieved using a van der Waals heterostructure device platform. Handedness-resolved optical reflection spectroscopy has been applied to probe the inter-LL transitions at individual valleys. The LL structure has been constructed. A doping-induced mass renormalization driven by the strong Coulomb interactions has also been observed. Our results open the door for studies of the unconventional LL physics and quantum Hall effect in monolayer TMDs.

13 pages, 4 figures

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Cited by in corpus (45)

• Evidence of high-temperature exciton condensation in 2D atomic double layers
• Engineering symmetry breaking in two-dimensional layered materials
• Continuous Mott transition in semiconductor moiré superlattices
• Strongly-Correlated Electron-Photon Systems
• Emerging Photoluminescence from the Dark-Exciton Phonon Replica in Monolayer WSe2
• Mapping twist-tuned multiband topology in bilayer WSe${}_2$
• Electron-exciton interactions in the exciton-polaron problem
• Luminescent emission of excited Rydberg excitons from monolayer WSe2
• Measurement of Conduction and Valence Bands g-factors in a Transition Metal Dichalcogenide Monolayer
• Valley Zeeman effect and Landau levels in Two-Dimensional Transition Metal Dichalcogenides
• Magnetooptics of layered two-dimensional semiconductors and heterostructures: progress and prospects
• Valley relaxation of resident electrons and holes in a monolayer semiconductor: Dependence on carrier density and the role of substrate-induced disorder
• Unveiling valley lifetimes of free charge carriers in monolayer WSe${}_2$
• Landau-quantized excitonic absorption and luminescence in a monolayer valley semiconductor
• Trion induced photoluminescence of a doped MoS2 monolayer
• Controlling exciton many-body states by the electric-field effect in monolayer MoS${}_2$
• Spontaneous valley polarization of interacting carriers in a monolayer semiconductor
• Excitonic signatures of ferroelectric order in parallel-stacked MoS${}_2$
• Many-body exciton and inter-valley correlations in heavily electron-doped WSe${}_2$ monolayers
• Hidden States and Dynamics of Fractional Fillings in tMoTe2 Moiré Superlattices
• Trions in MoS${}_2$ are quantum superpositions of intra- and intervalley spin states
• Valley-Filling Instability and Critical Magnetic Field for Interaction-Enhanced Zeeman Response in Doped WSe${}_2$ Monolayers
• Light-matter coupling and non-equilibrium dynamics of exchange-split trions in monolayer WS2
• Emergence of 6-particle "hexciton'' states in WS${}_2$ and MoSe${}_2$ monolayers
• Resonant exciton transfer in mixed-dimensional heterostructures for overcoming dimensional restrictions in optical processes
• Excitonic magneto-optics in monolayer transition metal dichalcogenides: From nanoribbons to two-dimensional response
• Optical detection of long electron spin transport lengths in a monolayer semiconductor
• Effects of dynamical dielectric screening on the excitonic spectrum of monolayer semiconductors
• Interplay of valley polarized dark trion and dark exciton-polaron in monolayer WSe2
• The relativistic dynamics of oppositely charged two fermions interacting with external uniform magnetic field
• Anomalous magneto-optical response and chiral interface of dipolar excitons at twisted valleys
• Magneto-optical conductivity of monolayer transition metal dichalcogenides in the presence of proximity-induced exchange interaction and external electrical field
• Resonant Raman scattering of surface phonon polaritons mediated by excitons in WSe${}_2$ films
• Exchange-enhanced spin-orbit splitting and its density dependence for electrons in monolayer transition metal dichalcogenides
• De Haas-van Alphen effect in graphene
• Probing the fractional quantum Hall phases in valley-layer locked bilayer MoS${}_2$
• Interacting holes in a gated WSe${}_2$ quantum channel: valley correlations and zigzag Wigner crystal
• High magnetic field spin-valley-split Shubnikov-de Haas oscillations in a WSe${}_2$ monolayer
• Valley Gapless Semiconductor: Models and Applications
• Interaction between the small gas molecules and the defective WSe2 monolayer
• Spontaneous Valley Splitting and Valley Pseudospin Field Effect Transistor of Monolayer VAgP2Se6
• Limits of funneling efficiency in non-uniformly strained 2D semiconductors
• How the dynamic of photo-induced gate screening complicates the investigation of valley physics in 2D materials
• Quantum oscillations of valley current driven by microwave irradiation in transition-metal dichalcogenide/ferromagnet hybrids
• Anomalous Landau level gaps near magnetic transitions in monolayer WSe${}_2$