Optical investigation of monolayer and bulk tungsten diselenide (WSe${}_2$) in high magnetic fields

Abstract

Optical spectroscopy in high magnetic fields $B\le 65$ T is used to reveal the very different nature of carriers in monolayer and bulk transition metal dichalcogenides. In monolayer WSe${}_2$, the exciton emission shifts linearly with the magnetic field and exhibits a splitting which originates from the magnetic field induced valley splitting. The monolayer data can be described using a single particle picture with a Dirac-like Hamiltonian for massive Dirac fermions, with an additional term to phenomenologically include the valley splitting. In contrast, in bulk WSe${}_2$ where the inversion symmetry is restored, transmission measurements show a distinctly excitonic behavior with absorption to the 1s and 2s states. Magnetic field induces a spin splitting together with a small diamagnetic shift and cyclotron like behavior at high fields, which is best described within the hydrogen model.

just accepted in Nano Letters http://pubs.acs.org/doi/abs/10.1021/acs.nanolett.5b00626 (equations corrected)

References in corpus (9)

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Cited by in corpus (28)

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• Exciton g-factors in monolayer and bilayer WSe${}_2$ from experiment and theory
• Luminescent emission of excited Rydberg excitons from monolayer WSe2
• Measurement of Conduction and Valence Bands g-factors in a Transition Metal Dichalcogenide Monolayer
• Magnetooptics of layered two-dimensional semiconductors and heterostructures: progress and prospects
• Magneto-optical transport properties of monolayer WSe2
• Brightening of spin- and momentum-dark excitons in transition metal dichalcogenides
• Strong manipulation of the valley splitting upon twisting and gating in MoSe${}_2$/CrI${}_3$ and WSe${}_2$/CrI${}_3$ van der Waals heterostructures
• Charge transfer and asymmetric coupling of MoSe${}_2$ valleys to the magnetic order of CrSBr
• Many-body exciton and inter-valley correlations in heavily electron-doped WSe${}_2$ monolayers
• Interlayer exciton valley polarization dynamics in large magnetic fields
• Probing valley filtering effect by Andreev reflection in zigzag graphene nanoribbon
• Ultrafast pseudospin quantum beats in multilayer WSe${}_2$ and MoSe${}_2$
• Revealing the nature of excitons in liquid exfoliated monolayer WS2
• Magneto photoluminescence measurements of tungsten disulphide monolayers
• Layer-dependent optically-induced spin polarization in InSe
• Magneto-optical conductivity of monolayer transition metal dichalcogenides in the presence of proximity-induced exchange interaction and external electrical field
• Rydberg excitons and polaritons in monolayer transition metal dichalcogenides in a magnetic field
• Landau-level composition of bound exciton states in magnetic field
• Single charge control of localized excitons in heterostructures with ferroelectric thin films and two-dimensional transition metal dichalcogenides
• High magnetic field spin-valley-split Shubnikov-de Haas oscillations in a WSe${}_2$ monolayer
• Extremely high excitonic $g$-factors in 2D crystals by alloy-induced admixing of band states
• Renormalization of the optical band gap through an effective Thirring interaction for massive Dirac-like electrons
• Magnetoexcitons and Massive Dirac Fermions in Monolayers of Transition Metal Dichalcogenides in a High Magnetic Field
• Gate-tunable spin-valley transport via carrier velocity in monolayer WSe${}_2$
• Excited-state band structure mapping