A5017082761- Laser Material Processing Techniques
- Plasmonic and Surface Plasmon Research
- Magnetic properties of thin films
- Gold and Silver Nanoparticles Synthesis and Applications
- Photonic and Optical Devices
- Photonic Crystals and Applications
- Force Microscopy Techniques and Applications
- Laser-induced spectroscopy and plasma
- Magnetic Properties and Applications
- Acoustic Wave Resonator Technologies
- Ultrasonics and Acoustic Wave Propagation
- Magneto-Optical Properties and Applications
- Laser-Matter Interactions and Applications
- Integrated Circuits and Semiconductor Failure Analysis
- Semiconductor Quantum Structures and Devices
- Metamaterials and Metasurfaces Applications
- Mechanical and Optical Resonators
- Ocular and Laser Science Research
- Quantum Information and Cryptography
- Ion-surface interactions and analysis
- Quantum optics and atomic interactions
- Nonlinear Optical Materials Studies
- Photorefractive and Nonlinear Optics
- Diamond and Carbon-based Materials Research
- Photoacoustic and Ultrasonic Imaging
Centre National de la Recherche Scientifique
2014-2024
École Polytechnique
2020-2024
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2020-2024
Laboratoire des Solides Irradiés
2022-2024
Ruhr University Bochum
2024
Institut Rayonnement-Matière de Saclay
2024
Université Sorbonne Nouvelle
2024
Institut des Molécules et Matériaux du Mans
2013-2022
Le Mans Université
2012-2022
ITMO University
2020
A silver-nanowire cavity is functionalized with CdSe nanocrystals and optimized towards quantum electrodynamics by varying the nanocrystal-nanowire distance $d$ length $L$. From modulation of nanocrystal emission modes a plasmon group velocity ${v}_{\mathrm{gr}}\ensuremath{\sim}0.5c$ derived. Efficient exciton-plasmon-photon conversion guiding demonstrated along modification in spontaneous rate coupled exciton-plasmon system.
Abstract Magneto-optical (MO) effects, viz. magnetically induced changes in light intensity or polarization upon reflection from transmission through a magnetic sample, were discovered over century and half ago. Initially they played crucially relevant role unveiling the fundamentals of electromagnetism quantum mechanics. A more broad-based relevance wide-spread use MO methods, however, remained quite limited until 1960s due to lack suitable, reliable easy-to-operate sources. The advent...
Ionization mechanisms in bulk dielectrics irradiated by single intense 50-fs-laser pulses are investigated ultrafast time-resolved imaging interferometry. Polarization-sensitive 6-photon ionization is shown to be the dominant mechanism fused silica and sapphire at intensities around $10\text{ }\text{ }\mathrm{TW}/{\mathrm{cm}}^{2}$. For both materials cross sections of found significantly higher for linear polarization than circular. Our experimental results corroborate an earlier...
The collective spontaneous emission of a fully inverted inhomogeneously broadened ensemble N two-level systems coupled to single-mode low-Q cavity is investigated numerically using Monte Carlo wave function technique. An intrinsically bi-exponential dynamics found when the time scales superradiance tau(sr) and inhomogeneous dephasing T2* approximately 1/Deltaomega(inh) become comparable: fast superradiant followed by slow subradiant decay. Experimental configurations ensembles quantum dots...
It is shown theoretically that a single few picoseconds long acoustic pulse can reverse magnetization in magneto-strictive material Terfenol-D. Following giant magneto-elastic changes of free energy density the vector kicked out local in-plane mininum and decays into another minimum. For duration significantly shorter than precession period $\tau_{ac}$<<$T_{prec}$, switching threshold determined by {\it area}, i.e. integral time domain, similar to coherent phenomena optics. Simulation...
Identifying materials with an efficient spin-to-charge conversion is crucial for future spintronic applications. The spin Hall effect a central mechanism as it allows the interconversion of and charge currents. Spintronic material research aims at maximizing its efficiency, quantified by angle $\Theta_{\textrm{SH}}$ spin-current relaxation length $\lambda_{\textrm{rel}}$. We develop all-optical method large sample throughput that us to extract Employing terahertz spectroscopy, we...
Fundamental interactions induced by lattice vibrations on ultrafast time scales have become increasingly important for modern nanoscience and technology. Experimental access to the physical properties of acoustic phonons in terahertz-frequency range over entire Brillouin zone is crucial understanding electric thermal transport solids their compounds. Here we report generation nonlinear propagation giant (1 per cent) strain pulses hybrid gold/cobalt bilayer structures probed with surface...
We generate in-plane magnetoelastic waves in nickel films using the all-optical transient grating technique. When performed on amorphous glass substrates, two dominant excitations can be resonantly driven by underlying elastic distortions, Rayleigh surface acoustic wave and skimming longitudinal wave. An applied field, oriented sample plane, selectively tunes coupling between magnetic precession one of waves, thus demonstrating selective excitation coexisting, large-amplitude waves....
A simple and robust setup for femtosecond time-resolved imaging interferometry of surfaces is described. The apparatus capable measuring both very small phase shifts (∼3×10−2 rad) amplitude changes(∼1%) with micrometer spatial resolution (∼1 μm). Interferograms are processed using a 2D-Fourier transform algorithm. We discuss the image formation physical interpretation measured interferograms. technique applied to measure transient changes GaAs surface irradiated intense laser pulses fluences...
Gain recovery dynamics are studied in electrically pumped quantum dot (QD) based semiconductor optical amplifiers (SOAs) after amplification of double femtosecond laser pulses using ultrafast pump-probe spectroscopy with heterodyne detection. The authors observe a distinct change gain the ground state when significant excited population is achieved. A complete found two 150fs 5ps time delay pass through SOA resonance to under high injection currents 80–100mA. obtained results open way for...
Optical excitation of surface plasmons in wet-chemically grown monocrystalline silver nanowires ( approximately 100 nm diameter and up to a few tens micrometers length) is studied by broadband imaging spectroscopy. Surface excited an incident light beam the so-called Kretschmann-Raether configuration give optical interference phenomena spectral domain. These oscillations are interpreted terms Fabry-Perot cavity modes for allow direct experimental determination plasmon group velocity losses.
We report about the synthesis and optical properties of a composite metal-insulator-semiconductor nanowire system which consists wet-chemically grown silver wire core surrounded by SiO2 shell controlled thickness, followed an outer highly luminescent CdSe nanocrystals. With microphotoluminescence (micro-PL) experiments, we studied exciton-plasmon interaction in individual nanowires analyzed spatially resolved nanocrystal emission for different length, SiO2-shell shape, pump power,...
The deposition of a dielectric overlayer on top Au/Co/Au multilayer films can significantly enhance the magnetic field induced modulation surface plasmon polariton (SPP) wave vector. This enhancement is analyzed as function thickness and associated SPP electromagnetic confinement redistribution. decrease in propagation distance taken into account by analyzing an adequate figure merit.
Abstract Surface magnetoelastic waves are coupled elastic and magnetic excitations that propagate along the surface of a material. Ultrafast optical techniques allow for non-contact excitation detection scheme while providing ability to measure both components individually. Here we describe simple setup suitable time resolved measurements high frequency waves, which is based on transient grating technique. The dynamics measured by diffracting probe laser pulse from long-wavelength spatially...
Driving the nonlinear magnetization dynamics in freestanding (100) iron membranes a perpendicular magnetic field by lowest-order high-Q acoustic cavity mode at ∼10 GHz frequency is simulated numerically solving Landau–Lifshitz–Gilbert equations. The analysis of large-amplitude precession within nanosecond time window displays transient chaotic induced hopping between metastable energy minima on complex anisotropy landscape. Fingerprints chaos should be observable femtosecond magneto-acoustic...
The application of quantum dot (QD) semiconductor optical amplifiers (SOAs) in above 100-Gbit Ethernet networks demands an ultrafast gain recovery on time scales similar to that the input pulse approximately 100 GHz repetition frequency. Microscopic scattering processes have act at shortest possible and mechanisms speeding up Coulomb be explored, controlled, exploited. We present a microscopic description by coupled polarization- population dynamics thermal nonequilibrium situation going...
Optical transmission spectroscopy on metal films with slit-groove pairs is conducted. Spectra of the light transmitted through slit exhibit Fabry-Perot-type interference fringes due to surface plasmons propagating between and groove. The spectral dependence period used determine group velocity flat gold silver surfaces.
The second-order photon correlation function g((2))(tau) of photons emitted by a continuously pumped ensemble N two-level systems coupled to single-mode optical cavity well below the lasing threshold is investigated theoretically. A giant bunching found for < 10 emitters as microscopic counterpart spontaneous emission noise driven quasi-periodic superradiant pulse sequences in macroscopic large numbers >> 1. phenomenon preserved even = 2 and can be explained cooperative evolution via dark...
Abstract Graphene is a unique material in the study of fundamental limits plasmonics. Apart from ultimate single-layer thickness, its carrier concentration can be tuned by chemical doping or applying an electric field. In this manner, electrodynamic properties graphene varied highly conductive to dielectric. supports strongly confined, propagating surface plasmon polaritons (SPPs) broad spectral range terahertz mid-infrared frequencies. It also possesses strong magneto-optical response and...
We review the recent progress in experimental and theoretical research of interactions between acoustic, magnetic plasmonic transients hybrid metal-ferromagnet multilayer structures excited by ultrashort laser pulses. The main focus is on understanding nonlinear aspects acoustic dynamics materials as well peculiarities optical magneto-optical response. For example, detection illustrated details probing static second harmonic generation gold-cobalt-silver trilayer Kretschmann geometry....
The nonlinear magneto-plasmonics aims to utilize plasmonic excitations control the mechanisms and taylor efficiencies of non-linear light frequency conversion at nanoscale. We investigate magnetic second harmonic generation in hybrid gold-cobalt-silver multilayer structures, which support propagating surface plasmon polaritons both fundamental frequencies. Using magneto-optical spectroscopy Kretschmann geometry, we show that huge modulation intensity is dominated by excitation frequency, as...