A5084004186- Laser Material Processing Techniques
- Phase-change materials and chalcogenides
- Advanced X-ray Imaging Techniques
- Solid-state spectroscopy and crystallography
- Material Science and Thermodynamics
- Laser-Matter Interactions and Applications
- Advanced Optical Imaging Technologies
- Advanced Fiber Laser Technologies
- Laser-induced spectroscopy and plasma
- X-ray Spectroscopy and Fluorescence Analysis
- Chalcogenide Semiconductor Thin Films
- Natural Language Processing Techniques
- Diamond and Carbon-based Materials Research
- Ion-surface interactions and analysis
- High-pressure geophysics and materials
- Advanced Measurement and Metrology Techniques
- Physical Unclonable Functions (PUFs) and Hardware Security
- Nonlinear Optical Materials Studies
- Infrared Thermography in Medicine
- Laser Design and Applications
- Advanced Surface Polishing Techniques
- Ocular and Laser Science Research
- Terahertz technology and applications
Université de Bordeaux
2017-2024
Universidad Carlos III de Madrid
2024
Centre Lasers Intenses et Applications
2020-2023
Centre National de la Recherche Scientifique
2020-2021
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2017-2021
CEA DAM Île-de-France
2017
Abstract Laser interaction with solids is routinely used for functionalizing materials' surfaces. In most cases, the generation of patterns/structures key feature to endow materials specific properties like hardening, superhydrophobicity, plasmonic color‐enhancement, or dedicated functions anti‐counterfeiting tags. A way generate random patterns, by means wrinkles on surfaces resulting from laser melting amorphous Ge‐based chalcogenide thin films, presented. These similar fingerprints, are...
Abstract The sub‐picosecond response of amorphous germanium telluride thin film to a femtosecond laser excitation is investigated using frequency‐domain interferometry and ab initio molecular dynamics. time‐resolved measurement the surface dynamics reveals shrinkage with dielectric properties’ faster than 300 fs. systematic simulations in non‐equilibrium conditions allow atomic configurations be retrieved for ionic temperature from 1100 K width electron distribution 0.001 1.0 eV. Local order...
Intense x-ray pulses can cause the non-thermal structural transformation of diamond. At SACLA XFEL facility, pump triggered this phase transition, and probe produced diffraction patterns. Time delays were observed from 0 to 250 fs, dose varied 0.9 8.0 eV/atom. The intensity (111), (220), (311) peaks decreased with time, indicating a disordering crystal lattice. From Debye-Waller analysis, rms atomic displacements perpendicular (111) planes be significantly larger than those (220) or planes....
We present the Aurore platform for ultrafast sciences. This is based on a unique 20 W, 1 kHz, 26 fs Ti:sapphire laser system designed reliable operation and high intensity temporal contrast. The specific design ensures stability in terms of pulse duration, energy, beam pointing necessary extended experimental campaigns. supplies 5 different beamlines, all dedicated to field: attosecond science (Aurore 1), phase transitions solids 2 3), luminescence 4), femtochemistry 5). technical...
The ultrafast electron energy transport is investigated in laser-heated warm dense copper a high flux regime (2.5±0.7×10^{13} W/cm^{2} absorbed). dynamics of the temperature retrieved from femtosecond time-resolved x-ray absorption near-edge spectroscopy near Cu L3 edge. A characteristic time ∼1 ps observed for increase average 100 nm thick sample. Data are well reproduced by two-temperature hydrodynamic simulations, which support dominated thermal conduction rather than ballistic electrons.
“Pop-art” like patterns resulting from the interaction of a single laser pulse focused on a-Ge based chalcogenide thin film capped with SiN layer are presented by Jérôme Gaudin and co-workers. These nondeterministic surface patterns, described in article number 2003032, wrinkles height less than 100 nm sub-micrometer periodicity, which depends impinging fluence. Application as physical unclonable functions is demonstrated using fast recognition algorithm.
X-ray Free Electron Laser (XFEL) radiation may transform diamond into graphite. Two pulses were used; the first as pump to trigger phase transition and second probe performing diffraction. The experiment was performed at SACLA XFEL facility beamline 3 experimental hutch 5. samples polycrystalline diamond. photon energies 7 10.5 keV, respectively, delay between varied from 0 286 fs. To provide a range of energy densities, focus adjusted 150 nm 1 um. (111), (220) (311) diffraction peaks...
X-ray laser-induced structural changes in silicon undergoing femtosecond melting have been investigated by using an x-ray pump-x-ray probe technique. The experimental results for different initial sample temperatures reveal that the onset time and speed of atomic disordering are independent temperature, suggesting equilibrium motion state does not play a pivotal role x-ray-induced ultrafast melting. By comparing observed time-dependence dedicated theoretical simulations, we interpret energy...
Laser filamentation is actively studied for its rich variety of applications, from supercontinuum generation to lightning control [1]. In air, femtosecond filaments result the self-focusing ultrashort light pulses that couple their own plasma channel and stay self-guided upon extended paths at high intensity levels. Driven by strong nonlinearities, these optical structures are able promote broadband THz-to-far-infrared radiation when using laser fields composed two colors, e.g., a...
A set of numerical models for the characterization laser processing applications is developed. The main physical and calculational features these are given along with some results on their comparison to experimental data other well established theoretical models. Special emphasis made suitability design practical implementation.