A5041275797- Diamond and Carbon-based Materials Research
- Metal and Thin Film Mechanics
- Organic Light-Emitting Diodes Research
- Thin-Film Transistor Technologies
- Crystallization and Solubility Studies
- Organic Electronics and Photovoltaics
- X-ray Diffraction in Crystallography
- High-pressure geophysics and materials
- Semiconductor Lasers and Optical Devices
- Liquid Crystal Research Advancements
- Semiconductor materials and devices
- Force Microscopy Techniques and Applications
- Synthesis and Properties of Aromatic Compounds
- Photonic and Optical Devices
- Advanced Optical Imaging Technologies
- Conducting polymers and applications
- Chemical and Physical Properties of Materials
- Interactive and Immersive Displays
- Image and Video Quality Assessment
- Biosensors and Analytical Detection
- Green IT and Sustainability
- Advanced Computing and Algorithms
- Phase-change materials and chalcogenides
- Quantum Dots Synthesis And Properties
- Advanced Photonic Communication Systems
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2019-2024
CEA Grenoble
2019-2024
Université Grenoble Alpes
2019-2024
CEA LETI
2019-2024
Institut polytechnique de Grenoble
2019-2020
Technicolor (France)
2003-2005
University of Cambridge
1999-2003
Laboratoire de physique de la matière condensée
1998-2001
Université de Picardie Jules Verne
2001
While the development of chiral molecules displaying circularly polarized luminescence (CPL) has received considerable attention, corresponding CPL intensity, g lum, hardly exceeds 10-2 at molecular level owing to difficulty in optimizing key parameters governing such a process. To address this challenge, we report here synthesis and chiroptical properties new family π-helical push-pull systems based on carbo[6]helicene, where latter acts as either electron acceptor or donor unit. This...
The main process responsible for the luminance degradation in organic light-emitting diodes (OLEDs) driven under constant current has not yet been identified. In this paper, we propose an approach to describe intrinsic mechanisms involved OLED aging. We first show that a stretched exponential decay can be used fit almost all versus time curves obtained different driving conditions. way, are able prove they described by employing single free parameter model. By using based on local relaxation...
Abstract Molecular designs merging circularly polarized luminescence (CPL) and thermally activated delayed fluorescence (CP‐TADF) using the concept of chiral perturbation appeared recently as a cornerstone for development efficient CP‐organic light emitting diodes (CP‐OLED). Such devices could strongly increase energy efficiency performances conventional OLED displays, in which 50% emitted is often lost due to use antiglare filters. In this context, herein, ten couples enantiomers derived...
The addition of silicon to hydrogenated amorphous carbon can have the advantageous effect lowering compressive stress, improving thermal stability its hydrogen, and maintaining a low friction coefficient up high humidity. Most experiments date been on carbon–silicon alloys (a-C1−xSix:H) deposited by rf plasma enhanced chemical vapor deposition. This method gives with sizeable hydrogen content only moderate hardness. Here we use density source known as electron cyclotron wave resonance...
Polymer-like and diamond-like hydrogenated amorphous carbon films, characterized by high spin concentrations of 1020 cm−3, have been studied multiple frequency electron paramagnetic resonance (EPR) spectroscopy at 9, 35, 94 GHz. Whereas the low-frequency measurements show only one single symmetric EPR line, high-frequency reveal anisotropic nature g tensor. They presence two different centers with tensors g∥(1)=2.005, g⊥(1)≈2.003, g∥(2)=2.010, g⊥(2)≈2.003. We attribute both to localized π...
We present a broadband free space light communication system using high-speed organic emitting diodes (OLEDs) as transmitters. Firstly, we report the design and bandwidth measurements of micro-OLEDs with active area <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$40 \times 40 ~\mu \text{m}^{2}$ </tex-math></inline-formula> . For this OLED, cut-off frequency up to 459 MHz is observed. Secondly, by applying...
Hydrogen stability has been investigated during wear tests in particular diamond-like carbon films deposited a dual electron cyclotron resonance radio frequency glow discharge plasma system, at two different substrate bias voltages equal to −30 and −600 V, for series I II, respectively. Combined infrared absorption elastic recoil detection analysis experiments are used fully characterize the their as-deposited state after tests. The results indicate clearly that total bonded hydrogen content...
The intrinsic stresses have been investigated in detail particular diamondlike carbon films prepared by chemical vapor deposition assisted electron cyclotron resonance plasma, as a function of the substrate bias and sample thickness relation with H content bonding. Combined infrared absorption, elastic recoil detection analysis, residual stress measurements are used to fully characterize their deposited state. results indicate clearly that both low high biased samples exhibit compressive...
In the field of augmented reality, there is a need for very bright color microdisplays to meet user specifications. Today, one most promising technology manufacture such displays involves blue micro-LED and quantum dots-based conversion layers. Despite recent progress, external power efficiencies (EPCE) these layers remain under ∼25%, below needs (>40%) reach white luminance 100,000 cd/m 2 . this work, we have synthesized CdSe x S 1-x nanoplatelet-based red green conversion, measured...
Liquid Crystals are birefringent materials, which address many applications such as visualization with Crystal Display (LCD) or beam shaping on Silicon devices (LCoS). Recently, several research teams proposed using liquid crystals in photonics applied to new kinds of projection displays. Augmented Reality (AR) is one the domains, could benefit from these developments, thanks necessity create active and transparent optical function. In this contribution, we present recent works at CEA Leti...
In our Augmented Reality (AR) project, we are investigating the use of a retinal projection display based on association pixelated holograms and dense distribution waveguides. We study gratings impregnated with liquid crystal to actively extract light from explore two extraction strategies: tuning refractive index contrast between grating teeth grooves erase diffraction effect changing waveguide cladding tune evanescence guided mode. Firstly, present discuss measurements efficiency...
The dielectric properties of wide and small gap amorphous carbon thin films were probed through capacitive spectroscopy measurements. We report a long time evolution, ranging between few hours days, the response films. reported behavior suggests very different hypotheses, such as facilitated diffusion polar impurities in porous films, or slowly relaxing electronic states lying at substrate/film interface built-in stress relaxation. In case contamination by adsorbed on voids surface, we...
We will show for the first time that PEDOT-PSS can be used to efficiently inject electrons into an n-doped organic layer. To do so, we use a graded n-doping profile, in order achieve best performance both electron injection and transport. our results using inverted OLED structure, ideal when a-Si active-matrix backplanes.
Efficient Light Emitting Diodes (LED) with a wide color gamut for high-resolution RGB display applications is still challenging objective state of the art technologies. The current industrial technology compromises narrow peaks emission device efficiency. In this work, we demonstrate CMOS compatible monolithic hybrid approach fabrication GaN Blue micro-LED co-integrated Green or Red top emitting OLED on 8'' epitaxy Si, LED sizes as low 5µm. This fulfills need good purity, while taking...