Polarization and time-resolved photoluminescence spectroscopy of excitons in MoSe2 monolayers

Abstract

We investigate valley exciton dynamics in MoSe2 monolayers in polarization- and time-resolved photoluminescence (PL) spectroscopy at 4K. Following circularly polarized laser excitation, we record a low circular polarization degree of the PL of typically $\le 5\%$. This is about 10 times lower than the polarization induced under comparable conditions in MoS2 and WSe2 monolayers. The evolution of the exciton polarization as a function of excitation laser energy and power is monitored in PL excitation (PLE) experiments. Fast PL emission times are recorded for both the neutral exciton of $\le 3$ ps and for the charged exciton (trion) of 12 ps.

4 pages, 3 figures

References in corpus (11)

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Cited by in corpus (17)

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• Probing the inter-layer exciton physics in a MoS${}_2$/MoSe${}_2$/MoS${}_2$ van der Waals heterostructure
• Optical response of monolayer, few-layer and bulk tungsten disulfide
• Highly Valley-Polarized Singlet and Triplet Interlayer Excitons in van der Waals Heterostructure
• Dark excitons and the elusive valley polarization in transition metal dichalcogenides
• Ultra-low power threshold for laser induced changes in optical properties of 2D Molybdenum dichalcogenides
• Optomechanical measurement of thermal transport in two-dimensional MoSe2 lattices
• Observation of exciton-exciton interaction mediated valley depolarization in monolayer MoSe${}_2$
• Superior valley polarization and coherence of 2s excitons in monolayer WSe2
• Valley polarized relaxation and upconversion luminescence from Tamm-Plasmon Trion-Polaritons with a MoSe2 monolayer
• Trion Species-Resolved Quantum Beats in MoSe2
• Valley Dynamics of Excitons in Monolayer Dichalcogenides
• Long-lived spin polarization in n-doped MoSe${}_2$ monolayers
• Theory of the Coherent Response of Magneto-Excitons and Magneto-Biexcitons in Monolayer Transition Metal Dichalcogenides
• Magnetic field mixing and splitting of bright and dark excitons in monolayer MoSe2
• Excitonic Transport and Intervalley Scattering in Exfoliated MoSe2 Monolayer Revealed by Four-Wave-Mixing Transient Grating Spectroscopy