A5008535159- 2D Materials and Applications
- Quantum Dots Synthesis And Properties
- Chalcogenide Semiconductor Thin Films
- Perovskite Materials and Applications
- Nanowire Synthesis and Applications
- Graphene research and applications
- Photonic and Optical Devices
- Molecular Junctions and Nanostructures
- Gas Sensing Nanomaterials and Sensors
- Plasmonic and Surface Plasmon Research
- MXene and MAX Phase Materials
- Mechanical and Optical Resonators
- Advanced Condensed Matter Physics
- Boron and Carbon Nanomaterials Research
- Ga2O3 and related materials
- Strong Light-Matter Interactions
- Conducting polymers and applications
- Electronic and Structural Properties of Oxides
Heriot-Watt University
2021-2024
Universitat de València
2016-2021
ORCID
2020
Manipulating properties of matter at the nanoscale is essence nanotechnology, which has enabled realization quantum dots, nanotubes, metamaterials, and two-dimensional materials with tailored electronic optical properties. Two-dimensional semiconductors have revealed promising perspectives in nanotechnology. However, tunability their physical challenging for studied until now. Here we show ability morphological manipulation strategies, such as nanotexturing or, limit, important surface...
Van der Waals materials offer a wide range of atomic layers with unique properties that can be easily combined to engineer novel electronic and photonic devices. A missing ingredient the van platform is two-dimensional crystal naturally occurring out-of-plane luminescent dipole orientation. Here we measure far-field photoluminescence intensity distribution bulk InSe InSe, WSe$_2$ MoSe$_2$. We demonstrate, support ab-initio calculations, layered flakes sustain excitons an intrinsic...
Abstract Numerous optical phenomena and applications have been enabled by nanophotonic structures. Their current fabrication from high refractive index dielectrics, such as silicon (Si) or gallium phosphide (GaP), pose restricting challenges while metals, relying on plasmons thus exhibiting ohmic losses, limit the achievable applications. An emerging class of layered, so‐called van der Waals (vdW), crystals is presented a viable nanophotonics platform in this work. The dielectric response 11...
The fundamental properties of an exciton are determined by the spin, valley, energy, and spatial wavefunctions Coulomb-bound electron hole. In van der Waals materials, these attributes can be widely engineered through layer stacking configuration to create highly tunable interlayer excitons with static out-of-plane electric dipoles, at expense strength oscillating in-plane dipole responsible for light-matter coupling. Here we show that in bi- tri-layer 2H-MoSe2 crystals exhibit...
The successful integration of few-layer thick hexagonal boron nitride (hBN) into devices based on two-dimensional materials requires fast and non-destructive techniques to quantify their thickness. Optical contrast methods Raman spectroscopy have been widely used estimate the thickness semiconductors semi-metals. However, they so far not applied insulators. In this work, we demonstrate ability optical hBN SiO2/Si substrates, which was also measured by atomic force microscopy. substrates...
Gallium selenide is one of the most promising candidates to extend window band gap values provided by existing two-dimensional semiconductors deep into visible potentially reaching ultraviolet. However, tunability its means quantum confinement effects still unknown, probably due poor nanosheet stability. Here, we demonstrate that optical GaSe nanosheets can be tuned ∼120 meV from bulk 8 nm thick. The luminescent response very thin (<8 nm) strongly quenched early oxidation. Oxidation favors...
The particular optical and electronic properties recently reported for 2D InSe depict this material as being very versatile future optoelectronic devices with tunable optimized functionalities. For its fundamental study the development of practical applications, rapid accurate identification methods atomically thin are essential. Here, we demonstrate an enhancement contrast between nanosheets underlying SiO2/Si substrate by illuminating a 40 nm wide bandpass filter centered at 500 nm....
Abstract The manipulation of light emitted by two-dimensional semiconductors grounds forthcoming technologies in the field on-chip communications. However, these require from so elusive out-of-plane photon sources to achieve an efficient coupling radiated into planar devices. Here we propose a versatile spectroscopic method that enables identification component dipoles. is based on selective in-plane and dipoles whispering gallery modes spherical dielectric microresonators, close contact...
Two-dimensional (2D) insulators are a key element in the design and fabrication of van der Waals heterostructures. They vital as transparent dielectric spacers whose thickness can influence both photonic, electronic, optoelectronic properties 2D devices. Simultaneously, they provide protection active layers heterostructure. For these critical roles, hexagonal Boron Nitride (hBN) is dominant choice due to its large bandgap, atomic flatness, low defect density, encapsulation properties....
The fundamental properties of an exciton are determined by the spin, valley, energy, and spatial wavefunctions Coulomb bound electron hole. In van der Waals materials, these attributes can be widely engineered through layer stacking configuration to create highly tunable interlayer excitons with static out-of-plane electric dipoles, at expense strength oscillating in-plane dipole responsible for light-matter coupling. Here we show that in bi- tri-layer 2H-MoSe$_2$ crystals exhibit...
Surface-to-volume ratio in two-dimensional (2D) materials highlights among their characteristics as an inherent and intrinsic advantage taking into account strong sensitivity to surface effects. For this reason, we have proposed work micromechanically exfoliated 2D nanosheets of InSe optical vapour sensor. As a proof concept, used 2-mercaptoethanol the chemical analyte phase monitor change photoluminescence (PL) before after exposure analyte. short times (at low concentration), found PL...
{\alpha}-RuCl$_3$, a narrow-band Mott insulator with large work function, offers intriguing potential as quantum material or charge acceptor for electrical contacts in van der Waals devices. In this work, we perform systematic study of the optical reflection contrast {\alpha}-RuCl$_3$ nanoflakes on oxidized silicon wafers and estimate accuracy imaging technique to assess crystal thickness. Via spectroscopic micro-ellipsometry measurements, characterize wavelength-dependent complex refractive...
α-RuCl3, a narrow-band Mott insulator with large work function, offers intriguing potential as quantum material or charge acceptor for electrical contacts in van der Waals devices. In this work, we perform systematic study of the optical reflection contrast α-RuCl3 nanoflakes on oxidized silicon wafers and estimate accuracy imaging technique to assess crystal thickness. Via spectroscopic micro-ellipsometry measurements, characterize wavelength-dependent complex refractive index varying...
In this work, we perform spectroscopic ellipsometry measurements at room temperature on mechanically exfoliated α-RuCl3 nanoflakes of different thickness for photon wavelengths ranging between 400 and 1000 nm. Our allow us to estimate the wavelength-dependent complex refractive index along crystal directions parallel perpendicular layers, which reveal an anisotropy in-plane out-of-plane optical properties material. results provide a valuable information about 2D flakes in visible near...
Abstract The manipulation of light emitted by two-dimensional semiconductors grounds forthcoming technologies in the field on-chip communications. However, these require from so elusive out-of-plane photon sources to achieve an efficient coupling radiated into planar devices. Here we propose a versatile spectroscopic method that enables identification component dipoles due selective in-plane and whispering gallery modes spherical dielectric microresonators, close contact them. We have...
Numerous optical phenomena and applications have been enabled by nanophotonic structures. Their current fabrication from high refractive index dielectrics, such as silicon or gallium phosphide, pose restricting challenges, while metals, relying on plasmons thus exhibiting ohmic losses, limit the achievable applications. Here, we present an emerging class of layered so-called van der Waals (vdW) crystals a viable nanophotonics platform. We extract dielectric response 11 mechanically...