Exciton dynamics in WSe2 bilayers

Abstract

We investigate exciton dynamics in 2H-WSe2 bilayers in time-resolved photoluminescence (PL) spectroscopy. Fast PL emission times are recorded for both the direct exciton with ${\tau }_D$ ~ 3 ps and the indirect optical transition with ${\tau }_i$ ~ 25 ps. For temperatures between 4 to 150 K ${\tau }_i$ remains constant. Following polarized laser excitation, we observe for the direct exciton transition at the K point of the Brillouin zone efficient optical orientation and alignment during the short emission time ${\tau }_D$. The evolution of the direct exciton polarization and intensity as a function of excitation laser energy is monitored in PL excitation (PLE) experiments.

4 pages, 3 figures

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Cited by in corpus (20)

• Polarization analysis of excitons in monolayer and bilayer transition-metal dichalcogenides
• Electrically tunable valley dynamics in twisted WSe${}_2$/WSe${}_2$ bilayers
• The role of momentum-dark excitons in the elementary optical response of bilayer WSe${}_2$
• High-temperature superfuidity of the two-component Bose gas in a TMDC bilayer
• Excitonic properties of semiconducting monolayer and bilayer MoTe2
• Novel valley depolarization dynamics and valley Hall effect of exciton in mono- and bilayer MoS${}_2$
• Spatially indirect intervalley excitons in bilayer WSe2
• Impact of indirect transitions on valley polarization in WS${}_2$ and WSe${}_2$
• Tuning exciton complexes in twisted bilayer WSe2 at intermediate misorientation
• Mapping of the energetically lowest exciton in bulk $1T$-HfS${}_2$
• Two dimensional semiconductors: optical and electronic properties
• Electric-field-tunable intervalley excitons and phonon replicas in bilayer WSe${}_2$
• Electrically controllable router of interlayer excitons
• High-temperature tunable superfluidity of polaritons in Xene monolayers in an optical microcavity
• Spectral asymmetry of phonon sideband luminescence in monolayer and bilayer WSe2
• Measurements of absolute bandgap deformation-potentials of optically-bright bilayer WSe${}_2$
• Robust Interlayer Exciton Interplay in Twisted van der Waals Heterotrilayer on a Broadband Bragg Reflector up to Room Temperature
• Moire-Engineered Excitonic Landscape and Phonon-Mediated Recombination in Twisted WSe2 Bilayers
• Finite-size effects in two-photon correlations of exciton Bose-Einstein condensates
• Emergence of non-uniform strain induced exciton species in homo- and heterobilayer transition metal dichalcogenides