A5031509388- Laser-Matter Interactions and Applications
- Advanced X-ray Imaging Techniques
- Particle Accelerators and Free-Electron Lasers
- Advanced Fiber Laser Technologies
- Laser-Plasma Interactions and Diagnostics
- Particle accelerators and beam dynamics
- Advanced Electron Microscopy Techniques and Applications
- Spectroscopy and Quantum Chemical Studies
- Nonlinear Optical Materials Studies
- Atomic and Molecular Physics
- Orbital Angular Momentum in Optics
- Gyrotron and Vacuum Electronics Research
- Magnetic Field Sensors Techniques
- Photonic Crystal and Fiber Optics
- Laser-induced spectroscopy and plasma
- Solid State Laser Technologies
- Magnetic Properties and Applications
- Quantum optics and atomic interactions
- Photorefractive and Nonlinear Optics
- Scientific Research and Discoveries
- Laser-Ablation Synthesis of Nanoparticles
- Nonlinear Dynamics and Pattern Formation
- X-ray Spectroscopy and Fluorescence Analysis
- Cardiac electrophysiology and arrhythmias
- Semiconductor Lasers and Optical Devices
Université Paris-Saclay
2017-2025
Laboratoire Interactions, Dynamiques et Lasers
2014-2025
CEA Paris-Saclay
2010-2025
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2009-2025
CY Cergy Paris Université
2025
Centre National de la Recherche Scientifique
2007-2024
Institut polytechnique de Grenoble
2024
Université Grenoble Alpes
2024
GIPSA-Lab
2024
Elettra-Sincrotrone Trieste S.C.p.A.
2013-2021
Optical vortices are currently one of the most intensively studied topics in optics. These light beams, which carry orbital angular momentum (OAM), have been successfully utilized visible and infrared a wide variety applications. Moving to shorter wavelengths may open up completely new research directions areas optical physics material characterization. Here, we report on generation extreme-ultraviolet with femtosecond duration carrying controllable amount OAM. From basic viewpoint, our...
Coherent x-ray diffractive imaging is a powerful method for studies on nonperiodic structures the nanoscale. Access to femtosecond dynamics in major physical, chemical, and biological processes requires single-shot diffraction data. Up now, this has been limited intense coherent pulses from free electron laser. Here we show that laser-driven ultrashort sources offer comparatively inexpensive alternative. We present measurements of patterns isolated nano-objects with single 20 fs pulse...
Exploring the dynamics of matter driven to extreme non-equilibrium states by an intense ultrashort X-ray pulse is becoming reality, thanks advent free-electron laser technology that allows development different schemes for probing response at variable time delay with a second pulse. Here we report generation two-colour ultraviolet pulses controlled wavelengths, intensity and timing seeding high-gain harmonic multiple independent pulses. The potential this new scheme demonstrated evolution...
FERMI is a seeded free-electron laser (FEL) facility located at the Elettra laboratory in Trieste, Italy, and now user operation with its first FEL line, FEL-1, covering wavelength range between 100 20 nm. The second FEL-2, high-gain harmonic generation double-stage cascade 20-4 nm, has also completed commissioning call been recently opened. An overview of typical operating modes presented.
In the context of x-ray lensless imaging, we present a recent approach for Fourier transform holography based on use extended references. Major advances shown here rely high signal efficiency and direct image reconstruction object performed by simple linear derivative. Moreover, holographic reference is easy to manufacture can be applied variety imaging experiments. Here demonstrate single-shot with table-top, laser-based coherent soft source. A spatial resolution 110 nm was obtained an...
Laser-heater systems are essential tools to control and optimize high-gain free-electron lasers (FELs) working in the x-ray wavelength range. Indeed, these induce a controllable increase of energy spread electron bunch. The heating suppresses longitudinal microbunching instability which otherwise would limit FEL performance. Here, we demonstrate that, through action instability, long-wavelength modulation beam induced by laser heater at low can persist until entrance into undulators. This...
High-order harmonic generation (HHG) from crystals is emerging as a new ultrashort source of coherent extreme ultraviolet (XUV) light. Doping the crystal structure can offer way to control properties. Here, we present study HHG enhancement in XUV spectral region an ionic crystal, using dopant-induced vacancy defects, driven by laser centered at wavelength 1.55 μm. Our numerical simulations based on solutions semiconductor Bloch equations and density-functional theory are supported our...
Abstract Polarization control is a key feature of light generated by short-wavelength free-electron lasers. In this work, we report the first experimental characterization polarization properties an extreme ultraviolet high gain laser operated with crossed polarized undulators. We investigate average degree and shot-to-shot stability analyze aspects such as existing possibilities for controlling switching state emitted light. The results are in agreement predictions based on Gaussian beams...
We present the main features of CITIUS, a new light source for ultrafast science, generating tunable, intense, femtosecond pulses in spectral range from IR to XUV. The XUV (about 10^5-10^8 photons/pulse 14-80 eV) are produced by laser-induced high-order harmonic generation gas. This radiation is monochromatized time-preserving monochromator, allowing also work with high-resolution bandwidth selection. tunable IR-UV (10^{12}-10^{15} 0.4-5.6 generated an optical parametric amplifier, which...
We demonstrate high-harmonic generation (HHG) in solids using a high-energy fiber laser system operating at 1550 nm. The driving few-cycle source consists of an erbium-doped chirped pulse amplifier combined with post-compression stage featuring gas-filled hollow-core photonic crystal (HC-PCF). nonlinear self-compression process the HC-PCF enables ultrashort pulses sub-50 fs durations and μJ-level energies 660 kHz repetition rate. Perturbative non-perturbative harmonics were subsequently...
We report on high-order harmonic generation (HHG) using a Ti:sapphire laser beam phase shaped with binary diffractive optical element (DOE) to create two spatially separated synchronized HHG sources at the focus of lens. Using full three-dimensional computations, we show numerically that dipole is imprinted in resulting far-field fringe pattern. corresponding experimental arrangement, measure aligned carbon dioxide. This arrangement robust, extremely stable, simple use, and gives highly...
Single photon laser enabled Auger decay (spLEAD) has been redicted theoretically [Phys. Rev. Lett. 111, 083004 (2013)] and here we report its first experimental observation in neon. Using coherent, bichromatic free-electron pulses, have detected the process coherently controlled angular distribution of emitted electrons by varying phase difference between two fields. Since spLEAD is highly sensitive to electron correlation, this a promising method for probing both correlation ultrafast hole...
We present the design and characterization of a double-configuration grating monochromator for spectral selection extreme-ultraviolet ultrafast pulses. Two geometries are joined in an instrument with two interchangeable diffracting stages, both used at grazing incidence: one gratings off-plane mount (OPM), other classical diffraction (CDM). The use stages gives great flexibility: OPM stage is sub-50 fs time response low resolution, while CDM 100-200 high resolution. temporal performances...
An understanding of collective effects is fundamental importance for the design and optimisation performance modern accelerators. In particular, an accelerator with strict requirements on beam quality, such as a free electron laser (FEL), highly dependent correspondence between simulation, theory experiments in order to correctly account effect coherent synchrotron radiation (CSR), other effects. A traditional approach simulation codes utilise analytic one-dimensional approximation CSR...
We demonstrate that emission of coherent transition radiation by a ∼1 GeV energy-electron beam passing through an Al foil is enhanced in intensity and extended frequency spectral range, the energy correlation established along synchrotron wakefield, presence proper electron optics delivery system. Analytical numerical models, based on experimental parameters collected at FERMI free laser (FEL), predict with two peaks ∼0.3 THz ∼1.5 THz, extending up to 8.5 above 20 dB w.r.t. main peak. Up...
In order to meet experimental conditions, the generation, evolution, and self-stabilization of optical dissipative light bullets from non-spherically-symmetric input pulses is studied. Steady-state solutions $(3+1)$-dimensional complex cubic-quintic Ginzburg-Landau equation are computed using variational approach with a trial function asymmetric respect three transverse coordinates. The analytical stability criterion extended systems without spherical symmetry, allowing determination domain...
We present single shot nanoscale imaging using a table-top femtosecond soft X-ray laser harmonic source at wavelength of 32 nm. show that the phase retrieval process in coherent diffractive critically depends on beam quality. Coherence and image fidelity are measured from single-shot diffraction patterns isolated nano-patterned slits. Impact flux, wave front coherence quality discussed. After improvements, final reconstruction is presented with spatial resolution 78 nm (half period) 20 fs shot.
We demonstrate experimentally the control of polarization (ellipticity and axis) femtosecond high-order harmonics. The method relies on a two-color ($\ensuremath{\omega}$ -- $2\ensuremath{\omega}$) configuration, where both $\ensuremath{\omega}$ $2\ensuremath{\omega}$ generating fields have linear polarizations with variable crossing angle. correlate our measurements conservation rules energy momentum accounting for harmonic generation in field. evidence that process, especially number...
In linac-driven free-electron lasers, colliders, and energy recovery linacs, a common way to compress the electron bunch kiloampere level is based upon implementation of magnetic dispersive element that converts particle deviation into path-length difference. Nonlinearities such process are usually compensated by enabling high harmonic rf structure properly tuned in amplitude phase. This approach however not straightforward, e.g., $C$-band $X$-band linacs. this Letter we demonstrate...
The role of the nuclear degrees freedom in nonlinear two-photon single ionization H_{2} molecules interacting with short and intense vacuum ultraviolet pulses is investigated, both experimentally theoretically, by selecting resonant vibronic intermediate neutral states. This high selectivity relies on narrow bandwidth tunability generated at FERMI free-electron laser. A sustained enhancement dissociative ionization, which even exceeds nondissociative observed controlled as one selects...
Abstract The optimal performance of high-brightness free-electron lasers (FELs) is limited by the microbunching instability, which can cause variations in both slice energy spread and longitudinal profile electron beams. In this paper, we perform 2D Fourier analysis full bunch phase space, such that modulations planes be studied simultaneously. Unlike standard 1D analysis, method able to reveal a folded would otherwise remain uncovered. Additionally, plasma oscillation between density also...
FERMI, based at Elettra (Trieste, Italy) is the first free electron laser (FEL) facility operated for user experiments in seeded mode. Another unique property of among other FEL sources, to allow control polarization state radiation. Polarization dependence study interaction coherent, high field, short-pulse ionizing radiation with matter, a new frontier potential wide range research areas. The measurement polarization-state VUV light from single-pass was performed FERMI FEL-1 52 nm-26 nm...