A5009907647- Gold and Silver Nanoparticles Synthesis and Applications
- Plasmonic and Surface Plasmon Research
- Electron and X-Ray Spectroscopy Techniques
- Quantum Dots Synthesis And Properties
- Laser-Matter Interactions and Applications
- Surface and Thin Film Phenomena
- Advanced Electron Microscopy Techniques and Applications
- Advanced Fiber Laser Technologies
- Ion-surface interactions and analysis
- Near-Field Optical Microscopy
- Carbon Nanotubes in Composites
- Spectroscopy and Laser Applications
- Advanced biosensing and bioanalysis techniques
- Metamaterials and Metasurfaces Applications
- Radiation Detection and Scintillator Technologies
- Organic Electronics and Photovoltaics
- Force Microscopy Techniques and Applications
- Advanced Semiconductor Detectors and Materials
- Electrochemical Analysis and Applications
- Semiconductor Quantum Structures and Devices
- Theoretical and Computational Physics
- Integrated Circuits and Semiconductor Failure Analysis
- Nanowire Synthesis and Applications
- Photonic and Optical Devices
- Diamond and Carbon-based Materials Research
CEA DAM Île-de-France
2020-2023
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2020-2023
Thales (France)
2020
Laboratoire de physique des Solides
2013-2018
Centre National de la Recherche Scientifique
2014-2018
Université Paris-Sud
2014-2018
Lund University
2014-2018
Laboratoire Ondes et Matière d'Aquitaine
2017
University of British Columbia
2017
Université de Bordeaux
2017
Plasmon modes of the exact same individual gold nanoprisms are investigated through combined nanometer-resolved electron energy-loss spectroscopy (EELS) and cathodoluminescence (CL) measurements. We show that CL only probes radiative modes, in contrast to EELS, which additionally reveals dark modes. The combination both techniques on particles thus provides complementary information also demonstrates although give rise very similar spatial distributions when probed by EELS or CL, their...
Electron energy loss spectroscopy (EELS) and cathodoluminescence (CL) have proved during the past few years to be tremendous tools study surface plasmons in metallic nanoparticles, thanks an extremely high spatial resolution combined with a broad spectral range. Despite their apparent close resemblance, qualitative differences between EELS CL been theoretically as well experimentally pinpointed. We demonstrate that these are recovered when comparing full electromagnetic local density of...
The local enhancement of few-cycle laser pulses by plasmonic nanostructures opens up for spatiotemporal control optical interactions on a nanometer and few-femtosecond scale. However, spatially resolved characterization plasmon dynamics poses major challenge due to the extreme length time scales involved. In this Letter, we experimentally demonstrate variations in during few strongest cycles plasmon-enhanced fields within individual rice-shaped silver nanoparticles. This was done using 5.5...
We present efficient high-order harmonic generation (HHG) based on a high-repetition rate, few-cycle, near infrared (NIR), carrier-envelope phase stable, optical parametric chirped pulse amplifier (OPCPA), emitting 6fs pulses with 9{\mu}J energy at 200kHz repetition rate. In krypton, we reach conversion efficiencies from the NIR to extreme ultraviolet (XUV) radiation order of ~10^{-6} less than 3{\mu}J driving energy. This is achieved by optimizing OPCPA for spatially and temporally clean...
We report on the identification and nanometer scale characterization over a large energy range of random, disorder-driven, surface plasmons in silver semicontinuous films embedded silicon nitride. By performing spatially resolved electron loss spectroscopy experiments, we experimentally demonstrate that these eigenmodes arise when become fractal, leading to emergence strong electrical fields (``hot spots'') localized few nanometers. show disorder-driven strongly depart from those usually...
A combination of coarse-grained molecular dynamics and kinetic Monte-Carlo modeling shows that electron transport in fullerene multi-adducts is limited by energetic disorder due to different isomers rather than structural disorder.
We propose a semianalytical formalism based on time-domain resonant-mode-expansion theory to analyze the ultrafast temporal dynamics of optical nanoresonators. compare theoretical predictions with numerical data obtained FDTD method, which is commonly used experiments in field. The comparison reveals that present (i) provides deeper physical insight onto response and (ii) much more computationally efficient. Since its implementation easy, formalism, albeit approximate, can be advantageously...
Due to a vanishing dipole moment, radial breathing modes in small flat plasmonic nanoparticles do not couple light and have be probed with near-field source, as electron energy loss spectroscopy (EELS). With increasing particle size, retardation gives rise coupling, enabling probing optically or by cathodoluminescence (CL). Here, we investigate single silver nanodisks diameters of 150–500 nm EELS CL an microscope quantify the EELS/CL ratio, which corresponds ratio full radiative damping...
We demonstrate the control of near-field localization within individual silver nanocubes through photoemission electron microscopy combined with broadband, few-cycle laser pulses. find that is concentrated at corners cubes, and it can be efficiently localized to different depending on polarization incoming light. The experimental results are confirmed by finite-difference time-domain simulations, which also provide an intuitive picture dependent in nanocubes.
We use cathodoluminescence (CL) spectroscopy in a transmission electron microscope to probe the radial breathing mode of plasmonic silver nanodisks. A two-mirror detection system sandwiching sample collects CL emission both directions, that is, backward and forward with respect beam trajectory. unambiguously identify spectral shift about 8 nm spectra acquired from sides show this asymmetry is induced by itself. By numerical simulations, we confirm observations underlying physical effect due...
While three-dimensional arrays of metallic nanoparticles in a dielectric matrix are promising candidates for plasmonic optical components and metamaterials, their fabrication remains challenging, the types structures that can be produced by conventional methods limited. The authors overcome these limitations using ion-beam irradiation to produce periodic arrangement prolate symmetric matrix, controlling both particle aspect ratio orientation. Applications aside, such structure is an ideal...
We demonstrate the control of multiphoton electron excitations in InAs nanowires (NWs) by altering crystal structure and light polarization. Using few-cycle, near-infrared laser pulses from an optical parametric chirped-pulse amplification system, we induce with controlled wurtzite (WZ) zincblende (ZB) segments. With a photoemission microscope, show that can selectively emission WZ or ZB segments same wire varying Developing ab initio GW calculations first to third order using...
Metal nanostructures can transfer electromagnetic energy from femtosecond laser pulses to the near-field down spatial scales well below optical diffraction limit. By combining few-femtosecond with photoemission electron microscopy, we study dynamics of induced few-cycle in individual bowtie nanoantennas. We investigate how depend on antenna size and exact shape resulting fabrication. Different are, as expected, measured for antennas different sizes. However, also detect comparable...
The displacement damage cross section of the neutron–GaN interaction is calculated in energy range from millielectronvolts to gigaelectronvolts. Different calculation methods are used and discussed estimate modeling uncertainty. nonionizing loss (NIEL) relative factors also deduced. Differences with neutron–silicon interactions presented, impacts on estimation total dose (TNID) levels evaluated as a function neutron energy.
We present a compact HHG source driven by few-cycle, few μJ, 200 kHz OPCPA system. Efficient harmonics are generated from Neon, Argon and Krypton with conversion efficiency of 4.0×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-8</sup> , 1.2×10 xmlns:xlink="http://www.w3.org/1999/xlink">-6</sup> 4.1×10 respectively.
The typical sizes at which confinement effects become predominant in optical properties range from few angstroms or nanometer (for excitons) to tens hundred of nanometers plasmons).As addition the leads intimately related size and geometry objects, it is thus important have tools able probe optical, morphological structural these scales.Optical microscopies spectroscopies can hardly deliver such spatial resolutions.Recently, electron as Electron Energy Loss Spectroscopy (EELS)...
The extraordinary character of Surface Plasmon modes disordered metallic systems has been predicted theoretically. We here demonstrate through Electron Energy Loss Spectroscopy that percolating fractal metal films sustain numerous strongly confined modes.
Fast electron based spectroscopies are often loosely compared to light scattering. By performing Electron Energy Loss Spectroscopy and Cathodoluminescence on single metallic nanoobjects, we show that these techniques nanometric probes of extinction
We provide an update on our high photon flux atto-second sources: XUV source with ~1011 photons/pulse for nonlinear experiments and a 200 kHz photons/second electron-imaging coincidence experiments.