Hot exciton transport in WSe2 monolayers

Abstract

We experimentally demonstrate hot exciton transport in h-BN encapsulated WSe2 monolayers via spatially and temporally resolved photoluminescence measurements at room temperature. We show that the nonlinear evolution of the mean squared displacement of the non-resonantly excited hot exciton gas is primarily due to the relaxation of its excess kinetic energy and is characterized by a density-dependent fast expansion that converges to a slower, constant rate expansion. We also observe saturation of the hot exciton gas' expansion rate at high excitation densities due to the balance between Auger-assisted hot exciton generation and the phonon-assisted hot exciton relaxation processes.

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Cited by in corpus (17)

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• Exciton optics, dynamics and transport in atomically thin semiconductors
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• Voltage-controlled long-range propagation of indirect excitons in van der Waals heterostructure
• Skew Scattering and Side Jump Drive Exciton Valley Hall Effect in Two-Dimensional Crystals
• Phonon-assisted Exciton Dissociation in Transition Metal Dichalcogenides
• Exciton diffusion in a hBN-encapsulated monolayer MoSe2
• Trion-trion annihilation in monolayer WS${}_2$
• Impact of charge transfer excitons on unidirectional exciton transport in lateral TMD heterostructures
• Spatiotemporal dynamics of free and bound excitons in CVD-grown MoS${}_2$ monolayer
• Imaging Seebeck drift of excitons and trions in MoSe2 monolayers
• Electron dynamics in a 2D nanobubble: A two-level system based on spatial density
• Two dimensional semiconductors: optical and electronic properties
• Exciton Transport under Periodic Potential in MoSe2/WSe2 Heterostructures
• Polariton transport in 2D semiconductors: Phonon-mediated transitions between ballistic, superdiffusive and exciton-limited regimes
• Microscopic Theory of Exciton-Exciton Annihilation in Two-Dimensional Semiconductors