Nano-optics of transition metal dichalcogenides and their van der Waals heterostructures with electron spectroscopies

Abstract

The outstanding properties of transition metal dichalcogenide (TMD) monolayers and their van der Waals (vdW) heterostructures, arising from their structure and the modified electron-hole Coulomb interaction in two-dimension, make them promising candidates for potential electro-optical devices. However, the production of reproducible devices remains challenging, partly due to variability at the nanometer to atomic scales. Thus, access to chemical, structural, and optical characterization at these lengthscales is essential. While electron microscopy and spectroscopy can provide chemical and structural data, accessing the optical response at the nanoscale through electron spectroscopies has been hindered until recently. This review focuses on the application of two electron spectroscopies in scanning (transmission) electron microscopes, namely cathodoluminescence and electron energy-loss spectroscopy, to study the nano-optics of TMD atomic layers and their vdW heterostructures. How technological advancements that can improve these spectroscopies, many of which are already underway, will make them ideal for studying the physics of vdW heterostructures at the nanoscale will also be discussed.

References in corpus (58)

• Atomically thin MoS2: A new direct-gap semiconductor
• Magic-angle graphene superlattices: a new platform for unconventional superconductivity
• 2D materials and van der Waals heterostructures
• Coupled spin and valley physics in monolayers of MoS2 and other group-VI dichalcogenides
• The structure of suspended graphene sheets
• Control of valley polarization in monolayer MoS2 by optical helicity
• Exciton Binding Energy and Nonhydrogenic Rydberg Series in Monolayer WS2
• Tuning superconductivity in twisted bilayer graphene
• Excitons in atomically thin transition metal dichalcogenides
• Observation of giant bandgap renormalization and excitonic effects in a monolayer transition metal dichalcogenide semiconductor
• Optical excitations in electron microscopy
• Observation of Moiré Excitons in WSe2/WS2 Heterostructure Superlattices
• Strong interlayer coupling in van der Waals heterostructures built from single-layer chalcogenides
• Stacking-engineered ferroelectricity in bilayer boron nitride
• The hot pick-up technique for batch assembly of van der Waals heterostructures
• Excitonic linewidth approaching the homogeneous limit in MoS2 based van der Waals heterostructures : accessing spin-valley dynamics
• Cleaning Interfaces in Layered Materials Heterostructures
• Fast pick up technique for high quality heterostructures of bilayer graphene and hexagonal boron nitride
• Interfacial ferroelectricity in marginally twisted 2D semiconductors
• Electron Beam Spectroscopy for Nanophotonics
• Irradiation of Nanostrained Monolayer WSe${}_2$ for Site-Controlled Single-Photon Emission up to 150 K
• Atomistic defect states as quantum emitters in monolayer MoS${}_2$
• Enhanced Light-Matter Interaction in Two-Dimensional Transition Metal Dichalcogenides
• Nanometer Scale Spectral Imaging of Quantum Emitters in Nanowires and Its Correlation to Their Atomically Resolved Structure
• 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${}_2$
• Integrated photonics enables continuous-beam electron phase modulation
• Cavity-mediated electron-photon pairs
• Filtering the photoluminescence spectra of atomically thin semiconductors with graphene
• Visualizing plasmon-exciton polaritons at the nanoscale using electron microscopy
• Spatially resolved quantum nano-optics of single photons using an electron microscope
• Electrically driven photon emission from individual atomic defects in monolayer WS2
• Exciton mapping at subwavelength scales in two-dimensional materials
• Angle-resolved cathodoluminescence spectroscopy
• Guide to optical spectroscopy of layered semiconductors
• Hyperspectral imaging of excitons within a moiré unit-cell with a sub-nanometer electron probe
• Efficient cathodoluminescence of monolayer transitional metal dichalcogenides in a van der Waals heterostructure
• Cathodoluminescence excitation spectroscopy: nanoscale imaging of excitation pathways
• Rotational and Dilational Reconstruction in Transition Metal Dichalcogenide Moiré Bilayers
• Dark trions govern the temperature-dependent optical absorption and emission of doped atomically thin semiconductors
• Electron-induced state conversion in diamond NV centers measured with pump-probe cathodoluminescence spectroscopy
• Magnetooptics of layered two-dimensional semiconductors and heterostructures: progress and prospects
• Probing exciton dispersions of freestanding monolayer WSe2 by momentum resolved electron energy loss spectroscopy
• Nanoscale modification of WS${}_2$ trion emission by its local electromagnetic environment
• Capturing 3D atomic defects and phonon localization at the 2D heterostructure interface
• Tailoring the dielectric screening in WS${}_2$-graphene heterostructures
• Investigation of the dispersion and the effective masses of excitons in bulk 2H-MoS2 using transition electron energy-loss spectroscopy
• Unveiling the coupling of single metallic nanoparticles to whispering-gallery microcavities
• Tip-induced excitonic luminescence nanoscopy of an atomically-resolved van der Waals heterostructure
• Substrate influence on transition metal dichalcogenide monolayer exciton absorption linewidth broadening
• Interlayer Charge Transfer and Defect Creation in Type I van der Waals Heterostructures
• $\mu$eV electron spectromicroscopy using free-space light
• Spectroscopic coincidence experiments in transmission electron microscopy
• Excitonic Absorption Signatures of Twisted Bilayer WSe${}_2$ by Electron Energy-Loss Spectroscopy
• Direct Optical-Structure Correlation in Atomically Thin Dichalcogenides and Heterostructures
• Engineering 2D material exciton lineshape with graphene/h-BN encapsulation
• Sub-to-super-Poissonian photon statistics in cathodoluminescence of color center ensembles in isolated diamond crystals
• Electroluminescence of monolayer WS${}_2$ in a scanning tunneling microscope: the effect of bias polarity on the spectral and angular distribution of the emitted light

Cited by in corpus (5)

• Roadmap for Photonics with 2D Materials
• Nanosecond nanothermometry in an electron microscope
• Excitons in epitaxially grown WS2 on Graphene: a nanometer-resolved EELS and DFT study
• An atlas of photonic and plasmonic materials for cathodoluminescence microscopy
• Characterization of WSe${}_2$ films using reflection Kikuchi diffraction in the scanning electron microscope and multivariate statistical analyses