A5107073326- Ultrasonics and Acoustic Wave Propagation
- Magnetic properties of thin films
- Force Microscopy Techniques and Applications
- Near-Field Optical Microscopy
- Magnetic Properties and Applications
- Metal and Thin Film Mechanics
- Acoustic Wave Resonator Technologies
- Integrated Circuits and Semiconductor Failure Analysis
- High-Temperature Coating Behaviors
- Metallic Glasses and Amorphous Alloys
- Acoustic Wave Phenomena Research
- High Entropy Alloys Studies
- Surface and Thin Film Phenomena
- Magnetic Properties of Alloys
- Mechanical and Optical Resonators
- Anodic Oxide Films and Nanostructures
- Optical Coatings and Gratings
- Photonic Crystals and Applications
- Diamond and Carbon-based Materials Research
- Ferroelectric and Piezoelectric Materials
- Metamaterials and Metasurfaces Applications
- Microstructure and Mechanical Properties of Steels
- Tendon Structure and Treatment
- Copper Interconnects and Reliability
- Numerical methods in engineering
Sorbonne Université
2013-2024
Institut des NanoSciences de Paris
2013-2024
Centre National de la Recherche Scientifique
1997-2024
Université Sorbonne Nouvelle
2024
GSI Helmholtz Centre for Heavy Ion Research
2019
Université de Poitiers
2013
Institut Pprime
2013
Université Paris Cité
2006
Physique et Mécanique des Milieux Hétérogènes
2003-2004
Laboratoire d'Informatique et d'Automatique pour les Systèmes
2003
CrN thin films with an N/Cr ratio of 95% were deposited by reactive magnetron sputtering onto (0 0 1) sapphire substrates. X-ray diffraction and pole figure texture analysis show (1 1 epitaxial growth in a twin domain fashion. By changing the nitrogen versus argon gas flow mixture deposition temperature, different surface morphologies ranging from grainy rough textures to flat smooth prepared. These parameters can also affect CrNx system, film compound between semiconducting metallic Cr2N...
We describe the use of micronic Hall sensors as magnetic-field profilometers with submicron resolution. The procedure involves deconvolution voltage maps produced by scanning field source over sensor, a probe microscope. response function an infinite cross is calculated analytically in two-dimensional case, using conformal mapping techniques. Various methods are presented and compared. used for deconvolutions, different effective sensor sizes tried. It shown that remaining main uncertainties...
Femtosecond pump-probe experiments have been carried out on circular single gold nanostructures lithographed a silicon substrate with diameters ranging from 1.1 down to 0.3 \ensuremath{\mu}m and thicknesses of 175 55 nm. Using three-dimensional finite-element simulations coupled the specific detection rule interferometric measurements, we illustrate effect intrinsic parameters such as size boundary conditions vibrational spectrum. The possibility using these artificial for acoustic...
The domain morphology in CoPt multilayers has been investigated by means of magnetic force microscopy for a broad range thickness parameters. Following hard-axis saturation, complex closure domains, isolated reversed and segmented fully developed stripe patterns are clearly identified down to widths the order 50 nm. Pending full numerical simulations, width behavior versus Co Pt thicknesses confronted predictions purely magnetostatic model. data consistent with existence single physically...
Picosecond ultrasonic measurements have been carried out on molybdenum-silicon multilayers in order to study their elastic effective-medium behavior using low-frequency acoustic echoes, and high-frequency response through localized surface modes. Taking into account the properties of silicon molybdenum thin films independently measured, we show that long-wavelength is well reproduced. Using an model includes only two constituent layers periodic cell without any interfacial zone, sound...
We used the picosecond ultrasonic technique to experimentally demonstrate negative refraction of surface acoustic waves in a two-dimensional phononic crystal. The sample is made square lattice circular voids drilled at thick silica substrate. parameter few micrometers. Broad band with Fourier components gigahertz range were excited. observed for Rayleigh frequencies second and propagating along direction $\ensuremath{\Gamma}\text{M}$ reduced Brillouin zone. then plane-wave expansion method...
Polymers with nanoparticle inclusions are attractive materials because physical properties can be tuned by varying size and volume fraction range. However, elastic behavior degrade at higher inclusion fractions when particle-particle contacts become important, sophisticated measurement techniques required to study this crossover. Here, we report on the mechanical of BaTiO3 nanoparticles (diameters < 10 nm) in a polymer (poly(methyl methacrylate)) matrix, deposited as films different...
Several different soft magnetic materials have been investigated by means of Magnetic Force Microscopy (MFM) using commercial Atomic Microscope (Nanoscope III) with slope detection. The observed contrast basically solenoidal magnetization distributions in nanocrystalline Fe-Permalloy multilayer and single-layer Permalloy thin film elements not only reveals wall locations, thus the subdivision volume into domains, but also a decomposition subdomains hitherto undocumented. A strong influence...
Acoustic imaging techniques are powerful, nondestructive tools used to perform elastic of systems. have a large variety applications in both industrial and fundamental research. wave generation the GHz range using picosecond acoustics has enabled development images with nanometric in-depth resolution. However, spatial lateral resolution for this technique is limited by laser spot size, which cannot be reduced below couple hundred nanometers due light diffraction. In paper, we report results...
We present a detailed experimental study on Mo${}_{1\ensuremath{-}x}$Si${}_{x}$ thin films, an archetypal alloy system combining metallic and semiconductor materials. The correlations between structure elastic response are comprehensively investigated. focus assessing trends for understanding the evolution of properties upon Si alloying in relation to structural state (crystalline vs amorphous), bonding character (metallic covalent), local atomic environment. By picosecond ultrasonics...
Domains were imaged by magnetic force microscopy (MFM) on materials where the domain size exceeds sample thickness three orders of magnitude. Selected samples are a magnetooptical medium and ultrathin cobalt films, all with perpendicular magnetization. A strong contrast is observed in both cases. This fact confronted to usual theory MFM image formation, which stray field from one body (tip or sample) sensed other, without altering magnetization distributions. It shown that such extreme...
An analysis of the equilibrium micromagnetic structure in multilayer films obtained by numerical computations is reported. The present work devoted to Co/Pt multilayers exhibiting perpendicular anisotropy and intermediate quality factor where comparison with previous experimental works can be done. A fair description magnetization behavior inside each magnetic layer stack proposed including surface applied field effects. In spite discontinuous aspect film absence any interlayer exchange...