Magneto-optics in transition metal diselenide monolayers

Abstract

We perform photoluminescence experiments at 4K on two different transition metal diselenide monolayers, namely MoSe2 and WSe2 in magnetic fields $B_z$ up to 9T applied perpendicular to the sample plane. In MoSe2 monolayers the valley polarization of the neutral and the charged exciton (trion) can be tuned by the magnetic field, independent of the excitation laser polarization. In the investigated WSe2 monolayer sample the evolution of the trion valley polarization depends both on the applied magnetic field and the excitation laser helicity, while the neutral exciton valley polarization depends only on the latter. Remarkably we observe a reversal of the sign of the trion polarization between WSe2 and MoSe2. For both systems we observe a clear Zeeman splitting for the neutral exciton and the trion of about $\pm 2$meV at $B_z\mp 9$T. The extracted Landé-factors for both exciton complexes in both materials are $g\approx -4$.

9 pages, 2 figures

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Cited by in corpus (13)

• Probing the influence of dielectric environment on excitons in monolayer WSe2: Insight from high magnetic fields
• Valley-spin polarized Landau levels in a monolayer semiconductor
• Exciton and trion dynamics in atomically thin MoSe2 and WSe2: effect of localization
• Probing the spin-polarized electronic band structure in monolayer transition metal dichalcogenides by optical spectroscopy
• Excitonic valley effects in monolayer WS${}_2$ under high magnetic fields
• Optical spectroscopy of excited exciton states in MoS2 monolayers in van der Waals heterostructures
• Intrinsic exciton states mixing and non-linear optical properties in transition metal dichalcogenide monolayers
• Magneto-photoluminescence of exciton Rydberg states in monolayer WSe${}_2$
• Opto-valleytronic imaging of atomically thin semiconductors
• Landau-quantized excitonic absorption and luminescence in a monolayer valley semiconductor
• Spectrum of exciton states in monolayer transition metal dichalcogenides: angular momentum and Landau levels
• Excitonic magneto-optics in monolayer transition metal dichalcogenides: From nanoribbons to two-dimensional response
• Large g factor in bilayer WS${}_2$ flakes