Dissociation of two-dimensional excitons in monolayer WSe2

Abstract

Two-dimensional (2D) semiconducting materials are promising building blocks for optoelectronic applications, many of which require efficient dissociation of excitons into free electrons and holes. However, the strongly bound excitons arising from the enhanced Coulomb interaction in these monolayers suppresses the creation of free carriers. Here, we probe and identify the main exciton dissociation mechanism through time- and spectrally-resolved photocurrent measurements in a monolayer WSe2 p-n junction. We find that under static in-plane electric field, excitons dissociate at a rate corresponding to the one predicted for the tunnel ionization of 2D Wannier-Mott excitons. This study is essential for the understanding of the optoelectronic photoresponse in of 2D semiconductors, and offers design rules for the realization of efficient photodetectors, valley-dependent optoelectronics and novel quantum coherent phases.

arXiv comment19 pages, 4 figures

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Cited by in corpus (41)

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• Photocurrent as a multi-physics diagnostic of quantum materials
• The ultrafast onset of exciton formation in 2D semiconductors
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• Intrinsic and Extrinsic Defect-related Excitons in TMDCs
• Interlayer excitons in van der Waals heterostructures: Binding energy, Stark shift, and field-induced dissociation
• Exciton optics, dynamics and transport in atomically thin semiconductors
• Stark shift of excitons and trions in two-dimensional materials
• Field-induced dissociation of two-dimensional excitons in transition-metal dichalcogenides
• Dark exciton-exciton annihilation in monolayer WSe${}_2$
• Anomalous Stark Shift of Excitonic Complexes in Monolayer Semiconductor
• Active control of excitonic strong coupling and electroluminescence in electrically driven plasmonic nanocavities
• Ultrafast photocurrents in MoSe${}_2$ probed by terahertz spectroscopy
• Photo-Induced Anomalous Hall Effect in Two-Dimensional Transition-Metal Dichalcogenides
• A colloquium on the variational method applied to excitons in 2D materials
• Generalized scaling law for exciton binding energy in two-dimensional materials
• In-Plane Electric Field Induced Orbital Hybridization of Excitonic States In Monolayer WSe2
• Spectral measurement of the breakdown limit of $\beta -G{a}_2{O}_3$ and tunnel ionization of self-trapped excitons and holes
• Tuning of impurity-bound interlayer complexes in a van der Waals heterobilayer
• Room Temperature Terahertz Electroabsorption Modulation by Excitons in Monolayer Transition Metal Dichalcogenides
• Monolayer transition metal dichalcogenides in strong magnetic fields: Validating the Wannier model using a microscopic calculation
• Giant enhancement of exciton radiative lifetime by ferroelectric polarization: The case of monolayer TiOCl${}_2$
• Anisotropic Stark shift, field-induced dissociation, and electroabsorption of excitons in phosphorene
• Phonon-assisted Exciton Dissociation in Transition Metal Dichalcogenides
• Optical Emission from Light-like and Particle-like Excitons in Monolayer Transition Metal Dichalcogenides
• High-harmonic spectroscopy of strongly bound excitons in solids
• Optically controlled single-valley exciton doublet states with tunable internal spin structures and spin magnetization generation
• Exciton dissociation in two-dimensional transition metal dichalcogenides: Excited states and substrate effects
• Exciton-exciton Interaction in Monolayer MoSe${}_2$ from Mutual Screening of Coulomb Binding
• Analytical Quantitative Semi-Classical Approach to the LoSurdo-Stark Effect and Ionization in 2D excitons
• Advancing excited-state properties of two-dimensional materials using a dielectric-dependent hybrid functional
• Dephasing of Strong-Field-Driven Floquet States Revealed by Time- and Spectrum-Resolved Quantum-Path Interferometry
• Probing the formation of dark interlayer excitons via ultrafast photocurrent
• Tunable effective masses of magneto-excitons in two-dimensional materials
• Dynamic polarizability of low-dimensional excitons
• Two dimensional semiconductors: optical and electronic properties
• Efficient ionization of two dimensional excitons by intense single cycle terahertz pulses
• Finite-difference time-domain simulation of strong-field ionization: Perfectly matched layer approach
• Trion Engineered Multimodal Transistors in Two dimensional Bilayer Semiconductor Lateral Heterostructures
• Macroscopic electro-optical modulation of solution-processed molybdenum disulfide
• Valley-controlled many-body exciton interactions in monolayer WSe${}_2$ phototransistors