Electrically Controlled Interfacial Charge Transfer Induced Excitons in MoSe2-WSe2 Lateral Heterostructure

Abstract

Controlling excitons and their transport in two-dimensional (2D) transition metal dichalcogenides (TMDs) heterostructures is central to advancing photonics and electronics on-chip integration. We investigate the controlled generation and manipulation of excitons and their complexes in monolayer (1L) MoSe2-WSe2 lateral heterostructure (LHS), directly grown via water-assisted chemical vapor deposition. Using a field-effect transistor design by incorporating a few-layer graphene back gate, single-layer graphene edge contact and encapsulation with few-layer hexagonal boron nitride, we achieve precise electrical tuning of exciton complexes and their transfer across 1D interfaces. At cryogenic temperatures (4 K), photoluminescence and photocurrent maps reveal the synergistic effect of local electric field and interface phenomena in the modulation of excitons, trions, and free carriers. We observe spatial variations in exciton and trion densities driven by exciton-trion conversion under electrical manipulation. The first-principle density functional theory calculation reveals significant band modification at the lateral interfaces and graphene-TMDs contact region. Furthermore, we demonstrate the versatility of 2D TMDS LHS in hosting and manipulating quantum emitters, achieving precise control over narrow-band emissions through modulating carrier injection and electrical biasing. This work extends the boundary of the present understanding of excitonic behaviour within lateral heterojunctions, highlighting the potential for controlled exciton manipulation across 1D interfaces and paving the way for next-generation electro-optical quantum devices.

5 Figs

References in corpus (35)

• Coupled spin and valley physics in monolayers of MoS2 and other group-VI dichalcogenides
• k.p theory for two-dimensional transition metal dichalcogenide semiconductors
• Exciton physics and device application of two-dimensional transition metal dichalcogenide semiconductors
• Excitonic linewidth approaching the homogeneous limit in MoS2 based van der Waals heterostructures : accessing spin-valley dynamics
• Sequential Edge-Epitaxy in 2D Lateral Heterostructures
• Exciton Radiative Lifetime in Transition Metal Dichalcogenide Monolayers
• Electrical control of interlayer exciton dynamics in atomically thin heterostructures
• Binding energies of exciton complexes in transition metal dichalcogenides and effect of dielectric environment
• Control of interlayer excitons in two-dimensional van der Waals heterostructures
• Irradiation of Nanostrained Monolayer WSe${}_2$ for Site-Controlled Single-Photon Emission up to 150 K
• Revealing the Biexciton and Trion-exciton Complexes in BN Encapsulated WSe2
• Radiative Lifetimes of Excitons and Trions in Monolayers of Metal Dichalcogenide MoS2
• Point Defects and Localized Excitons in 2D WSe2
• Direct exciton emission from atomically thin transition metal dichalcogenide heterostructures near the lifetime limit
• Localized inter-valley defect excitons as single-photon emitters in WSe${}_2$
• Emerging Photoluminescence from the Dark-Exciton Phonon Replica in Monolayer WSe2
• Entanglement of single-photons and chiral phonons in atomically thin WSe${}_2$
• Enhanced Optoelectronic Response in Bilayer Lateral Heterostructures of Transition Metal Dichalcogenides
• Electrical control of hybrid exciton transport in a van der Waals heterostructure
• Identifying defect-related quantum emitters in monolayer WSe${}_2$
• Exciton optics, dynamics and transport in atomically thin semiconductors
• Interface engineering of charge-transfer excitons in 2D lateral heterostructures
• Unveiling valley lifetimes of free charge carriers in monolayer WSe${}_2$
• Exciton spectroscopy and diffusion in MoSe2-WSe2 lateral heterostructures encapsulated in hexagonal boron nitride
• Dark-exciton driven energy funneling into dielectric inhomogeneities in two-dimensional semiconductors
• Microscopic origin of anomalous interlayer exciton transport in van der Waals heterostructures
• Substrate influence on transition metal dichalcogenide monolayer exciton absorption linewidth broadening
• Kapitza-resistance-like exciton dynamics in atomically flat MoSe${}_2$-WSe${}_2$ lateral heterojunction
• Twist angle dependent interlayer transfer of valley polarization from excitons to free charge carriers in WSe${}_2$/MoSe${}_2$ heterobilayers
• Evidence of Rotational Fröhlich Coupling in Polaronic Trions
• Engineering 2D material exciton lineshape with graphene/h-BN encapsulation
• Optical detection of long electron spin transport lengths in a monolayer semiconductor
• Chemically detaching hBN crystals grown at atmospheric pressure and high temperature for high-performance graphene devices
• Fano lines in the reflection spectrum of directly coupled systems of waveguides and cavities: measurements, modeling and manipulation of the Fano asymmetry
• Hyperspectral photoluminescence and reflectance microscopy of 2D materials

Cited by in corpus (3)

• Benchmarking the integration of hexagonal boron nitride crystals and thin films into graphene-based van der Waals heterostructures
• Impact of charge transfer excitons on unidirectional exciton transport in lateral TMD heterostructures
• Trion Engineered Multimodal Transistors in Two dimensional Bilayer Semiconductor Lateral Heterostructures