LASERIX est une plateforme de l’IJClab sur le campus de l’Université Paris Saclay. Le laser est une chaîne CPA de niveau 50 TW à 10 Hz. Des thématiques de recherche en rapport avec la physique des deux infinis sont menées en parallèle... more
LASERIX est une plateforme de l’IJClab sur le campus de l’Université Paris Saclay. Le laser est une chaîne CPA de niveau 50 TW à 10 Hz. Des thématiques de recherche en rapport avec la physique des deux infinis sont menées en parallèle avec une vocation affirmée d’ouverture à la formation. Nous présentons un panorama sur les sources XUV de lumière structurée, l’accélération laser plasma et des études prospectives sur l’étude des propriétés du vide soumis à un champ électromagnétique ultra-intense.
Research Interests: Physics and Humanities
The thin-film post-compression technique has the ability to reduce the pulse duration in PW-class lasers, increasing the peak power. Here, the nonlinear response of an increasingly available optical thermoplastic demonstrates enhanced... more
The thin-film post-compression technique has the ability to reduce the pulse duration in PW-class lasers, increasing the peak power. Here, the nonlinear response of an increasingly available optical thermoplastic demonstrates enhanced spectral broadening, with corresponding shorter pulse duration compared to fused silica glass. The thermoplastic can be used close to its damage threshold when refreshed using a roller mechanism, and the total amount of material can be varied by folding the film. As a proof-of-principle demonstration scalable to 10-PW, a roller mechanism capable of up to 6 passes through a sub-millimeter thermoplastic film is used in vacuum to produce two-fold post-compression of the pulse. The compact design makes it an ideal method to further boost ultrahigh laser pulse intensities with benefits to many areas, including driving high energy acceleration.
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International audienceWir präsentieren eine experimentelle Intensität und Wellenfront-Charakterisierung des Infrarot-Laser sowie den extremen ultravioletten Wirbel, der durch hohe harmonische Erzeugung in einem Medium der erweiterten... more
International audienceWir präsentieren eine experimentelle Intensität und Wellenfront-Charakterisierung des Infrarot-Laser sowie den extremen ultravioletten Wirbel, der durch hohe harmonische Erzeugung in einem Medium der erweiterten Generation erhalten wurde. In einer langen Fokussierungsgeometrie ermöglicht ein intensiver Wirbelstrahl, der durch phasenangepasste, absorptionsbegrenzte hohe harmonische Erzeugung in einer 15 mm langen mit Argon gefüllten Gaszelle erhalten wird, die Einzelschuss-Charakterisierung der Wirbelstruktur. Darüber hinaus validiert unsere Studie das Erhaltung Gesetz der Drehimpulses auch für ein solches Medium der erweiterten Generation.We present an experimental intensity and wavefront characterization of the infrared vortex driver as well as the extreme ultraviolet vortex obtained through high harmonic generation in an extended generation medium. In a loose focusing geometry, an intense vortex beam obtained through phase-matched absorption-limited high harm...
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We demonstrate the production of EUV vortex beams, and vector-vortex beams merging the helical phase of a vortex and the spatially variant polarization of a vector beam, both carrying large orbital angular momentum per photon.
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We demonstrate that high harmonic generation when driven by vortex driver contaminated with various orbital angular momentum (OAM) modes, the upconverted EUV harmonic deviates from perturbative conversion law to exhibit a spectrum of OAM... more
We demonstrate that high harmonic generation when driven by vortex driver contaminated with various orbital angular momentum (OAM) modes, the upconverted EUV harmonic deviates from perturbative conversion law to exhibit a spectrum of OAM orders.
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We present in this paper ongoing studies on seeded plasma-based soft X-ray lasers using the LASERIX facility. After an overview of the source setup and characteristics, we will discuss two prospects that might increase the interest of... more
We present in this paper ongoing studies on seeded plasma-based soft X-ray lasers using the LASERIX facility. After an overview of the source setup and characteristics, we will discuss two prospects that might increase the interest of these coherent soft X-ray sources. We have successfully generated harmonic beams carrying Orbital Angular momentum. We briefly present this experiment and discuss the remaining challenges for amplifying these kinds of beams in a plasma-based soft X-ray laser. In the second part, we present numerical results on harmonic seed amplification in conditions leading to Rabi oscillations. This regime is known to be a promising way to reach femtosecond pulses in the present plasma amplifiers. We will discuss the possibility of increasing the stability of such a regime by the introduction of a continuous refractive loss in the gain region.
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Research Interests: Physics and Beam matching
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Quantum electrodynamics predicts that the vacuum must behave as a nonlinear optical medium: the speed of light should be modified when the vacuum is stressed by intense electromagnetic fields. This optical phenomenon has not yet been... more
Quantum electrodynamics predicts that the vacuum must behave as a nonlinear optical medium: the speed of light should be modified when the vacuum is stressed by intense electromagnetic fields. This optical phenomenon has not yet been observed. The DeLLight (Deflection of Light by Light) experiment aims to observe the optically-induced index change of vacuum, a nonlinear effect which has never been explored. The experiment is installed in the LASERIX facility at IJCLab, which delivers ultra-short intense laser pulses (2.5 J per pulse, each of 30 fs duration, with a 10 Hz repetition rate). The proposal is to measure the refraction of a probe laser pulse when crossing a transverse vacuum index gradient, produced by a very intense pump pulse. The refraction induces a transverse shift in the intensity profile of the probe, whose signal is amplified by a Sagnac interferometer. In this article, we describe the experimental method and setup, and present the complete theoretical calculations...
Quantum electrodynamics predicts that the vacuum must behave as a nonlinear optical medium: the speed of light should be modified when the vacuum is stressed by intense electromagnetic fields. This optical phenomenon has not yet been... more
Quantum electrodynamics predicts that the vacuum must behave as a nonlinear optical medium: the speed of light should be modified when the vacuum is stressed by intense electromagnetic fields. This optical phenomenon has not yet been observed. The DeLLight (Deflection of Light by Light) experiment aims to observe the Kerr effect in vacuum, a nonlinear all-optical effect which has never been explored. The experiment is installed in the LASERIX facility at IJCLab, which delivers ultra-short intense laser pulses (2.5 J per pulse, each of 30 fs duration, with a 10 Hz repetition rate). The proposal is to measure the refraction of a probe laser pulse when crossing a transverse vacuum index gradient, produced by a very intense pump pulse. The refraction induces a transverse shift in the intensity profile of the probe, whose signal is amplified by a Sagnac interferometer. In this article, we describe the experimental method and setup, and present the complete theoretical calculations for th...
The ESCULAP project aims at studying external injection of low energy (10MeV) electrons in a plasma in the quasilinear regime. This facility will use the photo injector PHIL and the high power laser LASERIX. We will give a status report... more
The ESCULAP project aims at studying external injection of low energy (10MeV) electrons in a plasma in the quasilinear regime. This facility will use the photo injector PHIL and the high power laser LASERIX. We will give a status report of the preliminary work on the facility and the status of the two machines. We will also present the results of simulations showing the expected performances of the facility.
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... J. Meyer - ter-Vehn, H. Azechi. [2] BW Shore, MD Perry, JA Britten, RD Boyd, MD Feit, HT Nguye n, R. Chow, GE Loomis, and L.Li, Design of high -efficiency dielectric reflection gratings, J.Opt.Soc.Am. A 14,1124 (1997) [3] ISO ...
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ABSTRACT In most high power laser chains running at 1 µm since the 90's, the amplification media is Ti:sapphire because of its wide emission spectrum. With a single Ti:sapphire regenerative amplifier the mJ can be easily reached... more
ABSTRACT In most high power laser chains running at 1 µm since the 90's, the amplification media is Ti:sapphire because of its wide emission spectrum. With a single Ti:sapphire regenerative amplifier the mJ can be easily reached at 800 nm but at 1053 nm the gain is very low and an additional stage of amplification is needed to reach tens of mJ [1].
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High-power multicycle THz radiation is highly sought after with applications in medicine, imaging, spectroscopy, characterization and manipulation of condensed matter, and could support the development of next-generation compact... more
High-power multicycle THz radiation is highly sought after with applications in medicine, imaging, spectroscopy, characterization and manipulation of condensed matter, and could support the development of next-generation compact laser-based accelerators with applications in electron microscopy, ultrafast X-ray sources and sub-femtosecond longitudinal diagnostics. Multicycle THz-radiation can be generated by shooting an appropriate laser through a periodically poled nonlinear crystal, e.g. lithium niobate (PPLN). Unfortunately, the manufacturing processes of PPLNs require substantially strong electric fields $\mathcal{O}(10~kV/mm)$ across the crystal width to locally reverse the polarization domains; this limits the crystal apertures to below 1 cm. Damage threshold limitations of lithium niobate thereby limits the laser power which can be shone onto the crystal, which inherently limits the production of high-power THz pulses. Here we show that in the THz regime, a PPLN crystal can be...
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Nowdays, different applications required short bunches, with low energy spread and low emittances. On EXALT facility, we perform an experiment with a short (few100 femtosecond) laser pulse on a photocathode in a 3 GHz RF gun. We perform... more
Nowdays, different applications required short bunches, with low energy spread and low emittances. On EXALT facility, we perform an experiment with a short (few100 femtosecond) laser pulse on a photocathode in a 3 GHz RF gun. We perform the measurement of the single photon emission process with a copper cathode. We show that the longitudinal photoinjector model via transfer matrix is suitable for the reconstruction of the bunch duration even in short pulse mode with an increased accurracy charge below 20 pC. We clearly measure the parabolic profile in the energy spectrum resulting from blow out phenomena at the cathode due to strong space charge forces. Measurements are also compared with the Astra simulations.
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The plasma acceleration project ESCULAP (ElectronS CoUrts pour L’Accélération Plasma) aims at studying electrons injection into a laser plasma accelerator. This requires the injection of short electron bunches generated by the photo... more
The plasma acceleration project ESCULAP (ElectronS CoUrts pour L’Accélération Plasma) aims at studying electrons injection into a laser plasma accelerator. This requires the injection of short electron bunches generated by the photo injector PHIL (Photo injector at LAL) into a plasma wave by the high power femtosecond Laser LASERIX. As a first step we have studied how to synchronize PHIL and LASERIX. As these two machines had not been initially designed to work together, simple synchronization solutions were not available. We detail here the synchronisation scheme that we have tested and the experimental results obtained.
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We report temporal coherence measurement of solid-target plasma-based soft X-ray laser (XRL) in amplified spontaneous emission (ASE) mode. By changing the XRL pumping angle, we generate lasing at two-times higher electron density than the... more
We report temporal coherence measurement of solid-target plasma-based soft X-ray laser (XRL) in amplified spontaneous emission (ASE) mode. By changing the XRL pumping angle, we generate lasing at two-times higher electron density than the routine condition. A relatively shorter coherence time at a higher pumping angle indicates a clear spectral signature of higher electron density in the gain region. We probe the amplification dynamics of XRL in routine, and high electron density conditions to confirm gain-duration reduction resulting from ionization gating in the latter case. We also present recent results on the seeding of a vortex beam carrying orbital angular momentum (OAM) in XRL plasma. A small part of the high topological charge extreme ultraviolet (EUV) vortex is injected in XRL. These preliminary results suggest that the vortex seed indeed can be efficiently amplified. In the end, we propose a pathway towards the seeding of the complete vortex beam and wavefront characterization of the amplified beam.
We present a start to end (s2e) simulation of the Laserplasma Wake Field Accelerator (LPWA) foreseen as the ESCULAP project. We use a photo injector to produce a 5 MeV 10 pC electron bunch with a duration of 1 ps RMS, it is boosted to 10... more
We present a start to end (s2e) simulation of the Laserplasma Wake Field Accelerator (LPWA) foreseen as the ESCULAP project. We use a photo injector to produce a 5 MeV 10 pC electron bunch with a duration of 1 ps RMS, it is boosted to 10 MeV by a S-band cavity and then compressed to 74 fs RMS (30 fs FWHM) by a magnetic compression chicane (dogleg). After the dogleg, a quadrupole doublet and a triplet are utilized to match the Twiss parameters before injecting into the subsequent plasma wakefield. A 40 TW laser is used to excite plasma wakefield in the 10 cm plasma cell. An optimized configuration has been determined yielding at the plasma exit an electron beam at 180 MeV with energy spread of 4.2%, an angular divergence of 0.6 mrad and a duration of 4 fs.
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Thin-film compression (TFC) and the focusability of high-power laser pulses after self-phase modulation in thin films at transport intensities (∼1 TW/cm2) for petawatt laser systems is demonstrated. High-energy (∼296 mJ) laser pulses... more
Thin-film compression (TFC) and the focusability of high-power laser pulses after self-phase modulation in thin films at transport intensities (∼1 TW/cm2) for petawatt laser systems is demonstrated. High-energy (∼296 mJ) laser pulses are compressed from ∼55 fs to ∼31 fs. Additionally, the focusability of high-power (∼45–55 TW) flat-top laser pulses after spectral broadening in thin films is found to be largely maintained, showing only modest decreases in the energy contained in the central part of the focal spot. In light of these findings, TFC offers a method for moving toward single-cycle pulse durations at significantly higher energies than those found at present, and if beam instabilities can be mitigated, maybe even higher intensities.
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Seeded operation of a Neon-like Titanium plasma-based soft x-ray laser is described. The plasma amplifier is pumped using a variation of the classical grazing incidence pumping technique, combining a long low energy pulse followed by a... more
Seeded operation of a Neon-like Titanium plasma-based soft x-ray laser is described. The plasma amplifier is pumped using a variation of the classical grazing incidence pumping technique, combining a long low energy pulse followed by a main short pulse. Because the preformed plasma is underionized, a part of the main short pulse energy is used to ionized it to the lasing stage. Consequences of this feature on seeded laser properties are discussed.
Quantum electrodynamics predicts that the vacuum must behave as a nonlinear optical medium: the speed of light should be modified when the vacuum is stressed by intense electromagnetic fields. This optical phenomenon has not yet been... more
Quantum electrodynamics predicts that the vacuum must behave as a nonlinear optical medium: the speed of light should be modified when the vacuum is stressed by intense electromagnetic fields. This optical phenomenon has not yet been observed. The DeLLight (Deflection of Light by Light) experiment aims to observe the Kerr effect in vacuum, a nonlinear all-optical effect which has never been explored. The experiment is installed in the LASERIX facility at IJCLab, which delivers ultra-short intense laser pulses (2.5 J per pulse, each of 30 fs duration, with a 10 Hz repetition rate). The proposal is to measure the refraction of a probe laser pulse when crossing a transverse vacuum index gradient, produced by a very intense pump pulse. The refraction induces a transverse shift in the intensity profile of the probe, whose signal is amplified by a Sagnac interferometer. In this article, we describe the experimental method and setup, and present the complete theoretical calculations for th...
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ABSTRACT Various schemes have been recently proposed to factor numbers with physical systems. Based on electromagnetic fields interacting with quantum systems, they operate as analog computers. Here we present several experimental... more
ABSTRACT Various schemes have been recently proposed to factor numbers with physical systems. Based on electromagnetic fields interacting with quantum systems, they operate as analog computers. Here we present several experimental demonstrations based on ultrashort pulses interacting with rubidium atoms.
We have investigated a new scheme for laser plasma transient collisional soft x-ray lasers based on the use of an additional laser to produce the preplasma. Soft x-ray emission measurements made for different solid targets are presented... more
We have investigated a new scheme for laser plasma transient collisional soft x-ray lasers based on the use of an additional laser to produce the preplasma. Soft x-ray emission measurements made for different solid targets are presented and discussed. A significant enhancement of the SXRL emission as compared to double-pulse single-beam grazing incidence (DGRIP) using the same pump laser is reported for 13.9- and 32.6-nm SXRL wavelengths.
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An alternative, novel multiple pulse generation scheme was implemented directly after the optical compressor output of an x-ray pump laser. The new method uses a polarization sensitive thin film beam splitter and a half-wavelength wave... more
An alternative, novel multiple pulse generation scheme was implemented directly after the optical compressor output of an x-ray pump laser. The new method uses a polarization sensitive thin film beam splitter and a half-wavelength wave plate for tuning the energy ratio in the multiple short pulses. Based on this method, an extensive study was made of the running parameters for a grazing incidence pumped silver x-ray laser (XRL) pumped with a long pulse of 145 mJ in 6 ns at 532 nm and up to 1.45 J in few picoseconds at 810 nm. Fivefold enhancement in the emission of the silver XRL was demonstrated using the new pump method.
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The THz regime is widely appealing across many disciplines including solid-state physics, life sciences, and increasingly in particle acceleration. Multicycle THz pulses are typically formed via optical rectification in periodically poled... more
The THz regime is widely appealing across many disciplines including solid-state physics, life sciences, and increasingly in particle acceleration. Multicycle THz pulses are typically formed via optical rectification in periodically poled crystals. However the manufacturing procedures of these crystals limit their apertures to below ~1 cm, which from damage limitations of the crystal, limits the total pump power which can be employed, and ultimately, the total THz power which can be produced. Here we report on the simple in-house fabrication of a periodically poled crystal using ~300 μm thick wafers. Each wafer is consecutively rotated by 180∘ to support quasi-phase matching. We validate the concept with a Joule-class laser system operating at 10 Hz and measure up to 1.3 mJ of energy at 160 GHz, corresponding to an average peak power of approximately 35 MW and a conversion efficiency of 0.14%. In addition, a redshifting of the pump spectrum of ~50 nm is measured. Our results indi...
ABSTRACT We demonstrate the use of extreme ultra-violet (EUV) laboratory lasers in probing energy transport in laser irradiated solid targets. EUV transmission through targets containing a thin layer of iron (50 nm) encased in plastic... more
ABSTRACT We demonstrate the use of extreme ultra-violet (EUV) laboratory lasers in probing energy transport in laser irradiated solid targets. EUV transmission through targets containing a thin layer of iron (50 nm) encased in plastic (CH) after irradiation by a short pulse (35 fs) laser focussed to irradiances 3 × 1016 Wcm−2 is measured. Heating of the iron layer gives rise to a rapid decrease in EUV opacity and an increase in the transmission of the 13.9 nm laser radiation as the iron ionizes to Fe5+ and above where the ion ionisation energy is greater than the EUV probe photon energy (89 eV). A one dimensional hydrodynamic fluid code HYADES has been used to simulate the temporal variation in EUV transmission (wavelength 13.9 nm) using IMP opacity values for the iron layer and the simulated transmissions are compared to measured transmission values. When a deliberate pre-pulse is used to preform an expanding plastic plasma, it is found that radiation is important in the heating of the iron layer while for pre-pulse free irradiation, radiation transport is not significant.