Strongly interaction-enhanced valley magnetic response in monolayer WSe2

Abstract

Coulomb interaction between electrons lies at the heart of magnetism in solids. In contrast to conventional two-dimensional (2D) systems, electrons in monolayer transition metal dichalcogenides (TMDs) possess coupled spin and valley degrees of freedom by the spin-orbit interaction. The electrons are also strongly interacting even in the high-density regime because of the weak dielectric screening in two dimensions and a large band mass. The combination of these properties presents a unique platform for exploring spin and valley magnetism in 2D electron liquids. Here we report an observation by magneto-photoluminescence spectroscopy of a nonlinear valley Zeeman effect, correlated with an over fourfold enhancement in the exciton g-factor in monolayer WSe2. The effect occurs when the Fermi level crosses the spin-split upper conduction band, corresponding to a change of the spin-valley degeneracy from 2 to 4. The enhancement increases, shows no sign of saturation as the sample temperature decreases. Our result suggests the possibility of rich many-body ground states in monolayer TMDs with multiple internal degrees of freedom.

11 pages, 3 figures

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Cited by in corpus (29)

• Emerging Photoluminescence from the Dark-Exciton Phonon Replica in Monolayer WSe2
• Spin-Polarized Electrons in Monolayer MoS${}_2$
• Spin-Valley Locking Effect in Defect States of Monolayer MoS${}_2$
• Ambipolar Landau levels and strong band-selective carrier interactions in monolayer WSe${}_2$
• Ab-initio studies of exciton $g$ factors: Monolayer transition metal dichalcogenides in magnetic fields
• Screening magnetic two-dimensional atomic crystals with nontrivial electronic topology
• Moiré-trapped interlayer trions in a charge-tunable WSe${}_2$/MoSe${}_2$ heterobilayer
• Magnetooptics of layered two-dimensional semiconductors and heterostructures: progress and prospects
• Excitation-induced transition to indirect band gaps in atomically thin transition metal dichalcogenide semiconductors
• Unveiling valley lifetimes of free charge carriers in monolayer WSe${}_2$
• Optical control of valley Zeeman effect through many-exciton interactions
• Landau-quantized excitonic absorption and luminescence in a monolayer valley semiconductor
• Charge transfer and asymmetric coupling of MoSe${}_2$ valleys to the magnetic order of CrSBr
• Controlling exciton many-body states by the electric-field effect in monolayer MoS${}_2$
• Spontaneous valley polarization of interacting carriers in a monolayer semiconductor
• Twist angle dependent interlayer transfer of valley polarization from excitons to free charge carriers in WSe${}_2$/MoSe${}_2$ heterobilayers
• Electric Dipole Spin Resonance of 2D Semiconductor Spin Qubits
• Trions in MoS${}_2$ are quantum superpositions of intra- and intervalley spin states
• Possible Realization and Protection of Valley-Polarized Quantum Hall Effect in Mn/WS2
• Valley-Filling Instability and Critical Magnetic Field for Interaction-Enhanced Zeeman Response in Doped WSe${}_2$ Monolayers
• Large g factor in bilayer WS${}_2$ flakes
• Rotons in Optical Excitation Spectra of Monolayer Semiconductors
• Theory of the Coherent Response of Magneto-Excitons and Magneto-Biexcitons in Monolayer Transition Metal Dichalcogenides
• Quadrupolar and Dipolar Excitons in Bilayer 2$H$-MoSe${}_2$
• Magneto-Optical Measurements of the Negatively Charged 2$s$ Exciton in WSe${}_2$
• Retrieval of fundamental material parameters of monolayer transition metal dichalcogenides from experimental exciton energies: An analytical approach
• Probing strong interactions in p-type few-layer WSe${}_2$ by density-dependent Landau level crossing
• Enhanced Valley Zeeman Splitting in Fe-Doped Monolayer MoS2
• Strong intervalley correlation induced a magnetic order transition in monolayer ${\text{MoS}}_2$