A5005072772- Advanced Fiber Laser Technologies
- Nonlinear Photonic Systems
- Photonic and Optical Devices
- Photorefractive and Nonlinear Optics
- Laser-Matter Interactions and Applications
- Magnetic confinement fusion research
- Optical Network Technologies
- Quantum optics and atomic interactions
- Orbital Angular Momentum in Optics
- Terahertz technology and applications
- Laser-Plasma Interactions and Diagnostics
- Optical Polarization and Ellipsometry
- Semiconductor Lasers and Optical Devices
- Neural Networks and Reservoir Computing
- Optical and Acousto-Optic Technologies
- Fusion materials and technologies
- Superconducting Materials and Applications
- Nonlinear Waves and Solitons
- Gyrotron and Vacuum Electronics Research
- Nonlinear Optical Materials Studies
- Porphyrin and Phthalocyanine Chemistry
- Laser-induced spectroscopy and plasma
- Optical Coatings and Gratings
- Nuclear Physics and Applications
- Spectroscopy and Laser Applications
National Agency for New Technologies, Energy and Sustainable Economic Development
2022-2024
Institut de Recherche sur la Fusion par Confinement Magnétique
2024
CEA Cadarache
2024
University of Rome Tor Vergata
2024
Culham Science Centre
2024
Culham Centre for Fusion Energy
2024
Université Grenoble Alpes
2023
Laboratoire des Écoulements Géophysiques et Industriels
2023
Sapienza University of Rome
2007-2021
Franche-Comté Électronique Mécanique Thermique et Optique - Sciences et Technologies
2019
Abstract In 2021 JET exploited its unique capabilities to operate with T and D–T fuel an ITER-like Be/W wall (JET-ILW). This second major campaign (DTE2), after DTE1 in 1997, represented the culmination of a series enhancements—new fusion diagnostics, new injection capabilities, refurbishment plant, increased auxiliary heating, in-vessel calibration 14 MeV neutron yield monitors—as well as significant advances plasma theory modelling community. DTE2 was complemented by sequence isotope...
Abstract An overview is presented of the progress since 2021 in construction and scientific programme preparation Divertor Tokamak Test (DTT) facility. Licensing for building has been granted at end 2021. Cat. A radiologic source also 2022. The toroidal field magnet system progressing. prototype 170 GHz gyrotron produced it now under test on FALCON design vacuum vessel, poloidal coils civil infrastructures completed. shape first DTT divertor agreed with EUROfusion to different plasma exhaust...
The discovery of chirped pulse amplification has led to great improvements in laser technology, enabling energetic beams be compressed durations tens femtoseconds and focused a few micrometers. Protons with energies MeV can accelerated using, for instance, target normal sheath acceleration on secondary targets. Under such conditions, nuclear reactions occur, the production radioisotopes suitable medical application. use high-repetition lasers produce isotopes is competitive conventional...
Partially coherent sources with radial coherence are proposed. They present a circularly symmetric intensity profile and degree of whose absolute value only depends on the angular difference between two considered points. In particular, source is completely at pairs points belonging to same radius. The modal structure such determined in general case, conditions derived under which field propagated paraxial approximation remains radially any transverse plane. cases, dependence correlation...
We experimentally demonstrate simultaneous phase and group velocity locking of fundamental generated second harmonic pulses in Lithium Niobate, under conditions material mismatch. In phase-mismatched, pulsed generation addition to a reflected signal two forward-propagating are also at the interface between linear order nonlinear material: first pulse results from solution homogeneous wave equation, propagates expected dispersion; is inhomogeneous phase-locked trapped by pump pulse, follows...
We study adiabatic light transfer in systems of two coupled waveguides with spatially varying detuning the propagation constants, providing an analogy to quantum phenomena rapid passage (RAP) and two-state stimulated Raman (two-state STIRAP). Experimental demonstration using a photoinduction technique confirms robust broadband character structures that act as directional couplers beam splitters, respectively.
A simple optical system is proposed to generate full-Poincaré beams (FPBs), i.e. presenting all possible states of (total) polarization across their transverse section. The method consists in focusing a uniformly polarized laser beam onto uniaxial crystal having its optic axis parallel the propagation impinging beam. approximated model used obtain analytical expression at output crystal. then proved be FPB. By changing state input field, are still obtained, but different distributions...
Abstract Within the 9th European Framework programme, since 2021 EUROfusion is operating five tokamaks under auspices of a single Task Force called ‘Tokamak Exploitation’. The goal to benefit from complementary capabilities each machine in coordinated way and help developing scientific output scalable future largre machines. programme this ensures that ASDEX Upgrade, MAST-U, TCV, WEST JET (since 2022) work together achieve objectives Missions 1 2 Roadmap: i) demonstrate plasma scenarios...
We report the observation of spatial confinement a pump beam into photorefractive solitonic channel induced by luminescence [luminescence soliton (LISS)]. Trapped beams have been obtained in erbium doped lithium niobate crystals at concentrations as high 0.7 mol % erbium. By pumping 980 nm, ions emit photons 550 nm two-step absorption, wavelength which can be absorbed and originates effect. The generates same time background illumination reaching steady-state regime.
Adding a twist phase term to the cross-spectral density (CSD) function of partially coherent source can be done if and only resulting remains nonnegative definite. Constraints on that guarantee validity CSD have been derived for Twisted Gaussian Schell-model (TGSM) sources. Here, an infinite family higher-order TGSM sources is introduced, whose CSDs are expressed as products standard times Hermite polynomials arbitrary orders suitable arguments. All members present same all them...
A technique for the room temperature electro-optic detection of coherent low-frequency radiation, typically in far infrared or terahertz (THz) range, is proposed. It relies on a longitudinally running electric field grating probed by phase-matched Raman–Nath diffraction higher frequency wave. The expected probe wave diffracted intensity background-free and proportional to desired signal intensity. As an example, we present model calculations probing monochromatic THz radiation using organic...
It is shown that light transfer between two evanescently coupled optical waveguides can be interrupted when strong interaction with a third waveguide induced. In the strong-interaction regime reactivated upon proper detuning of propagation constants. These phenomena easily understood using analog Autler-Townes splitting and electromagnetically induced transparency from atomic physics. Experimental demonstration provided photoinduced reconfigurable waveguides.
Ethology has shown that animal groups or colonies can perform complex calculation distributing simple decision-making processes to the group members. For example ant optimize trajectories towards food by performing both a reinforcement (or cancellation) of pheromone traces and switch from one path another with stronger pheromone. Such ant's be implemented in photonic hardware reproduce stigmergic signal processing. We present innovative, completely integrated X-junctions realized using...
In this paper, the study of a plasma diagnostic system based on THz time domain spectroscopy technique is presented. Such could potentially probe large part electromagnetic spectrum currently covered by several other diagnostics in single measurement. This feature, keeping mind basic requirements for nuclear fusion experiments, such as robustness and hard environment applicability, well durability low maintenance, makes great interest. A conceptual design THz-TDS has been developed, starting...
We present numerical and experimental analyses showing the formation of (2+1)D spatial photorefractive solitons at visible wavelengths in electrically biased lithium niobate crystals for ordinary extraordinary light polarizations. Similarly sized self-trapped beams are observed both polarizations, despite polarization-dependent electro-optic coefficients. The tensorial character photovoltaic effect is shown to play a key role. soliton-induced waveguides able properly guide telecommunication...
In this paper, we experimentally demonstrate collisions between two copropagating parallel coherent beams inside the photorefractive semiconductor iron doped indium phosphide (InP:Fe) at λ=1064 nm.
In this paper we report self-trapping of subnanojoule femtosecond near-infrared beams in photonic-grade undoped bulk lithium niobate under application an external dc electric field. We show that the phenomenon occurs thanks to photorefractive effect induced by a weak second-harmonic component generated large velocity mismatch. It offers way extend niobate's response spectrum for peak intensity lower than $1\phantom{\rule{0.3em}{0ex}}\mathrm{GW}∕{\mathrm{cm}}^{2}$, which is three orders...
Abstract Stigmergy is a communication method based on changing the surrounding environment according to reference feedbacks. It typical within animal colonies that are able process even complex information by releasing signals into environment, which subsequently received and processed other elements of colony. For example, ants searching for food leave traces pheromone, like Hansel Gretel’s breadcrumbs, along way. When found, they return anthill reinforcing this pheromone trace as signal...
By exploiting a Mach–Zehnder interferometer, the r33electro-optic coefficient of erbium-bulk-doped lithium niobate crystals grown by Czochralski technique was measured depending on erbium content. Ther33 decreases with concentration. Such trend has been connected both reduction lattice parameter, high resolution x-ray diffraction, and increase defects.
In this paper, we develop a simple technique to identify material texture from far, by using polarization-resolved imaging. Such can be easily implemented into industrial environments, where fast and cheap sensors are required. The has been applied both isotropic references (Teflon bar) anisotropic samples (wood). By studying the radiance of illuminated linearly polarized light, different specific behaviours identified for samples, in terms multipolar emission linear dichroism, which fibre...
We experimentally investigate the formation of self-confined beams in lithium niobate crystals which are doped bulk with erbium. Samples have been grown by Czochralski method erbium nominal concentrations varying range 0.0–0.7 mol% melt. The speeds beam confinement depend on applied bias and intensity, as expected, but doping level well. incorporation influences both electro-optic coefficient photovoltaic field. A very general dependence confined waist refractive index change was derived,...
Spatial and temporal locking of fundamental second harmonic pulses was realized by means photorefractive nonlinearity highly mismatched generation. Due to the presence both phase-locked unlocked pulses, a twin simultonic state observed. Simultonic filamentation occurring at high pumping rates allowed us determine relation between simulton's waist its intensity.