A5037041678- ZnO doping and properties
- GaN-based semiconductor devices and materials
- Strong Light-Matter Interactions
- Ga2O3 and related materials
- Thermal Radiation and Cooling Technologies
- Semiconductor Quantum Structures and Devices
- Copper-based nanomaterials and applications
- Plasmonic and Surface Plasmon Research
- Photonic and Optical Devices
- Electronic and Structural Properties of Oxides
- Mechanical and Optical Resonators
- Semiconductor materials and devices
- Advanced Fiber Laser Technologies
- Metal and Thin Film Mechanics
- Gas Sensing Nanomaterials and Sensors
- Nanowire Synthesis and Applications
- Metamaterials and Metasurfaces Applications
- Chalcogenide Semiconductor Thin Films
- Quantum Dots Synthesis And Properties
- Electron and X-Ray Spectroscopy Techniques
- Quantum and electron transport phenomena
- Quantum Mechanics and Non-Hermitian Physics
- Plasma Diagnostics and Applications
- Orbital Angular Momentum in Optics
- Semiconductor Lasers and Optical Devices
Centre de Recherche sur l'Hétéro-Epitaxie et ses Applications
2016-2025
Centre National de la Recherche Scientifique
2016-2025
Sorbonne Université
2022-2025
National University of Singapore
2022-2025
Nanyang Technological University
2022-2025
Université Côte d'Azur
2017-2025
Observatoire de la Côte d’Azur
2025
UMI MajuLab
2024-2025
Centre for Quantum Technologies
2020-2024
Université de Montpellier
2023
Zinc oxide (ZnO), with its excellent luminescent properties and the ease of growth nanostructures, holds promise for development photonic devices. The recent advances in ZnO nanorods are discussed. Results from both low temperature high approaches presented. techniques which presented include metal–organic chemical vapour deposition (MOCVD), phase epitaxy (VPE), pulse laser (PLD), vapour–liquid–solid (VLS), aqueous (ACG) finally electrodeposition technique as an example a selective approach....
Oxide electronic materials provide a plethora of possible applications and offer ample opportunity for scientists to probe into some the exciting intriguing phenomena exhibited by oxide systems interfaces. In addition already diverse spectrum properties, nanoscale form oxides provides new dimension hitherto unknown due increased surface-to-volume ratio.
Upon reflection, modulate phase Metasurfaces provide a platform to fabricate optical devices in compact form much thinner than their corresponding bulk components. Recognizing that metasurfaces are also open systems interacting with environment, Song et al . designed metasurface exploits those non-Hermitian properties such they can encircle an exceptional point. Subsequent scattering from point was shown be polarization dependent, thus providing additional control knob designing for wave...
We report exciton-polariton condensation in a new family of fully hybrid ZnO-based microcavity demonstrating the best-quality ZnO material available (a bulk substrate), large quality factor (~4000) and Rabi splittings (~240 meV). Condensation is achieved between 4 300 K for excitonic fractions ranging 17% 96%, which corresponds to tuning mass, lifetime, interaction constant by 1 order magnitude. demonstrate mode switching polariton branches allowing, just controlling pumping power, tune...
Abstract Exceptional points (EPs) can achieve intriguing asymmetric control in non-Hermitian systems due to the degeneracy of eigenstates. Here, we present a general method that extends this specific response EP photonic address any arbitrary fully-polarized light. By rotating meta-structures at EP, Pancharatnam-Berry (PB) phase be exclusively encoded on one circular polarization-conversion channels. To wavefront, superpose optical signals originating from two orthogonally polarized -yet...
Holography holds tremendous promise in applications such as immersive virtual reality and optical communications. With the emergence of metasurfaces, planar components that have remarkable ability to precisely manipulate amplitude, phase, polarization light on subwavelength scale expanded potential holography. However, realization metasurface-based full-color vectorial holography remains particularly challenging. Here, we report a general approach utilizing modified Gerchberg–Saxton...
The bandgap and band-edge effective mass of single crystal cadmium oxide, epitaxially grown by metal-organic vapor-phase epitaxy, are determined from infrared reflectivity, ultraviolet/visible absorption, Hall effect measurements. Analysis simulation the optical data, including effects band nonparabolicity, Moss-Burstein filling renormalization, reveal room temperature values 2.16±0.02eV 0.21±0.01m0 respectively.
The valence-band density of states single-crystalline rock-salt CdO(001), wurtzite $c$-plane ZnO, and rock- salt MgO(001) are investigated by high-resolution x-ray photoemission spectroscopy. A classic two-peak structure is observed in the VB-DOS due to anion $2p$-dominated valence bands. Good agreement found between experimental results quasi-particle-corrected density-functional theory calculations. Occupied shallow semicore $d$ levels CdO ZnO. While these exhibit similar spectral features...
The polar nature of the wurtzite crystalline structure GaN and ZnO results in existence a spontaneous electric polarization within these materials their associated alloys (Ga,Al,In)N (Zn,Mg,Cd)O. polarity has also important consequences on stability different crystallographic surfaces, this becomes especially when considering epitaxial growth. Furthermore, internal fields may adversely affect properties optoelectronic devices but is used as potential advantage for advanced electronic...
Hexagonal boron nitride is not only a promising functional material for the development of two-dimensional optoelectronic devices but also good candidate quantum sensing thanks to presence emitters in form atom-like defects. Their exploitation technologies necessitates understanding their coherence properties as well sensitivity external stimuli. In this work, we probe strain configuration vacancy centers (VB-) created by ion implantation h-BN flakes wide-field spatially resolved optically...
Full wavefront control by photonic components requires that the spatial phase modulation on an incoming optical beam ranges from 0 to 2{\pi}. Because of their radiative coupling environment, all are intrinsically non-Hermitian systems, often described reflection and transmission matrices with complex eigenfrequencies. Here, we show Parity-Time symmetry breaking -- either explicit or spontaneous moves position Zero singularities real axis upper part frequency plane. A universal 2{\pi}-phase...
Solid-state defects susceptible of spin manipulation hold great promise for scalable quantum technology. To broaden their utility, operation at room temperature and emission in the telecom wavelength range are desired, eliminating cryogenic requirements leveraging existing optical fiber infrastructure transmission information. that end, we report single-photon emitters (SPEs) gallium nitride (GaN) exhibit optically detected magnetic resonance (ODMR) temperature. The analysis ODMR as a...
We demonstrate polariton lasing in a bulk ZnO planar microcavity under non-resonant optical pumping at small negative detuning (δ ∼ −1/6 the 130 meV vacuum Rabi splitting) and temperature of 120 K. The strong coupling regime is maintained threshold since coherent nonlinear emission from lower branch occurs zero in-plane wavevector well below uncoupled cavity mode. contribution multiple localized modes above non-thermal statistics show that system far-from-equilibrium regime, likely related...
An energy gap between the valence and conduction band is defining property of a semiconductor, size plays crucial role in design semiconductor devices. We show that presence two-dimensional electron gas near to surface can significantly alter its through many-body effects caused by high density, resulting much smaller than bulk. Apart from reconciling number disparate previous experimental findings, results suggest an entirely new route spatially inhomogeneous band-gap engineering.
Temperature-dependent optical absorption, Hall effect, and infrared reflectance measurements have been performed on as-grown post-growth annealed CdO films grown by metal organic vapor phase epitaxy sapphire substrates. The evolution of the absorption edge conduction electron plasmon energy with temperature has modeled, including effects arising from Burstein-Moss shift bandgap renormalization. zero-temperature fundamental direct band effective mass determined to be 2.31 ± 0.02 eV...
The ideal single-photon source displaying high brightness and purity, emission on-demand, mature integration, practical communication wavelength (i.e., in the telecom range), operating at room temperature does not exist yet. In 2018, a new was discovered gallium nitride (GaN) showing potential thanks to its emission, record-high brightness, good operation temperature. Despite all these assets, coupling photonic structures has been achieved so far. this article, we make first step direction....
The valence band offset of ZnO/AlN heterojunctions is determined by high resolution x-ray photoemission spectroscopy. ZnO found to be 0.43±0.17 eV below that AlN. Together with the resulting conduction 3.29±0.20 eV, this indicates a type-II (staggered) line up exists at heterojunction. Using III-nitride offsets and transitivity rule, for ZnO/GaN ZnO/InN are derived as 1.37 1.95 respectively, significantly higher than previously values.
In contrast to conventional semiconductors, native defects, hydrogen impurities, and surface states are all found be donors in $n$-type CdO. Using this as a model system, the electrical behaviors of dopants, semiconductors unified by single energy level, charge neutrality giving much insight into current materials allowing band-structure engineering scheme for obtaining desired custom electronic properties new compound semiconductors.
Abstract Optical whispering gallery mode (WGM) resonances have been observed in zinc oxide micro‐ and nanowire cavities. Using model calculations, the experimentally spectrum was reproduced. The effect has for wire radii between 100 nm 10 µm corresponding to angular numbers from 1 about 250. used determine refractive index of wires as a function photon energy temperature. Under high excitation conditions, WGM lasing observed. Two methods calculating complex resonant modes are presented:...
The electronic structure of well-ordered single-crystal thin films CdO(100) has been studied using angle-resolved photoemission spectroscopy. Quantized electron subbands are observed above the valence-band maximum. existence these states provides evidence an intrinsic accumulation space-charge layer near CdO surface, interpretation supported by coupled Poisson-Schr\"odinger calculations. origin result is discussed in terms bulk band calculated quasiparticle-corrected density-functional...
We present a lattice-dynamics study of rocksalt cadmium oxide (CdO). use Raman scattering to investigate series high-quality CdO epilayers grown on sapphire substrates by means metal-organic vapor phase epitaxy. Two main features are found dominate the spectra CdO: sharp peak at ∼265 cm−1 and broad feature ∼390 cm−1. To assign these other weaker second-order that appear in spectra, we have carried out an ab initio calculation phonon dispersion CdO. From calculated two-phonon density states...
Top-down fabricated GaN nanowires, 250 nm in diameter and with various heights, have been used to experimentally determine the evolution of strain along vertical direction 1-dimensional objects. X-ray diffraction photoluminescence techniques obtain profile inside nanowires from their base top facet for both initial compressive tensile strains. The relaxation behaviors derived optical structural characterizations perfectly match numerical results calculations based on a continuous media...
Nitride materials (AlN, GaN, InN and their alloys) are commonly used in optoelectronics, high-power high-frequency electronics. Polarity is the essential characteristic of these materials: when grown along c-direction, films may exhibit either N- or metal-polar surface, which strongly influences physical properties. The possibility to manipulate polarity during growth allows establish unique nitride thin nanowires for existing applications but also opens up new opportunities device...
Voigt points represent propagation directions in anisotropic crystals along which optical modes degenerate, leading to a single circularly polarized eigenmode. They are particular class of exceptional points. Here, we report the fabrication and characterization dielectric, microcavity based on nonpolar ZnO that implements non-Hermitian system mimics behavior natural crystals. We prove exceptional-point nature by monitoring complex-square-root topology mode eigenenergies (real imaginary...
The interface properties between nonpolar ZnO and sapphire have been studied using high resolution transmission electron microscopy. Two orientations are investigated: a- m-orientations corresponding to [112¯0] [101¯0] crystallographic directions. After the definition of epitaxial relationships resulting initial lattice mismatch, we show that can be grown on with perfectly flat interfaces. Geometrical misfit dislocations observed at ZnO/sapphire their density gives residual strain in layer....