Luca Volpe

Universidad de Salamanca · centro de Laseres Pulsados (CLPU)

Shock Ignition is a two-step scheme to reach Inertial Confinement Fusion, where the precompressed fuel capsule is ignited by a strong shock driven by an intense laser pulse at intensity ∼ 10 ¹⁶ W/cm ² . In this report we detail the results of an experiment designed to investigate the origin of hot electrons (HE) in laser-plasma interaction at inten...

Strong electromagnetic pulses (EMPs) are generated from intense laser interactions with solid-density targets and can be guided by the target geometry, specifically through conductive connections to the ground. We present an experimental characterization by time- and spatial-resolved proton deflectometry of guided electromagnetic discharge pulses a...

We present a parametric study based on 1-D particle-in-cell (PIC) simulations conducted with the objective of understanding the interaction of intense lasers with near-critical non-uniform density gas targets. Specifically, we aim to find an optimal set of experimental parameters regarding the interaction of a $\lambda_L$ = 0.8 $\mu$m, $I_L =10^{20...

Laser-plasma driven accelerators have become reliable sources of low-emittance, broadband and multi-species ion beams, presenting cutoff energies above the MeV-level. We report on the development, construction, and experimental test of an angle-resolved Thomson Parabola (TP) spectrometer for laser-accelerated multi-MeV ion beams which is able to di...

Strong electromagnetic pulses (EMP) are generated from intense laser interactions with solid-density targets, and can be guided by the target geometry, specifically through conductive connections to the ground. We present an experimental characterization, by time- and spatial-resolved proton deflectometry, of guided electromagnetic discharge pulses...

We present experimental results for the controlled mitigation of electromagnetic pulses (EMP) produced in interactions of the 1PW high-power 30fs Ti:Sa laser VEGA-3 with matter. This study aims at the band of very high frequencies (VHF), notably hundreds of MHz, comprising the fundamental cavity modes of the rectangular VEGA-3 vacuum chamber. We de...

Ion stopping in warm dense matter is a process of fundamental importance for the understanding of the properties of dense plasmas, the realization and the interpretation of experiments involving ion-beam-heated warm dense matter samples, and for inertial confinement fusion research. The theoretical description of the ion stopping power in warm dens...

We present an experimental study and prospects of high repetition rate (HRR) targetry for the interaction of relativistic laser pulses at intensities of several 1e20 W/cm2 with solid density targets. So-called tape targets are rewound in vacuum conditions in order to always expose a new section of undisturbed surface to the laser focus. The require...

A novel detector based on a polycrystalline diamond sensor is here employed in an advanced time-of-flight scheme for the characterization of energetic ions accelerated during laser-matter interactions. The optimization of the detector and of the advanced TOF methodology allow to obtain signals characterized by high signal-to-noise ratio and high dy...

In August 2021, at the National Ignition Facility of the Lawrence Livermore National Laboratory in the USA, a 1.35 MJ fusion yield was obtained. It is a demonstration of the validity of the Inertial Confinement Fusion approach to achieve energy-efficient thermonuclear fusion in the laboratory. It is a historical milestone that the scientific commun...

We recently started systematic recording of Electromagnetic Pulses (EMP) at CLPU. First activity concerns the range from low frequencies (9kHz) to ultra high frequencies (2GHz), a band that is known for radio transmission on the lower end and mobile phone networks on the higher end. At CLPU, the EMP is caused by the interaction of the VEGA laser pu...

A novel detector based on a polycrystalline diamond sensor is here employed in an advanced Time-Of-Flight scheme for the characterization of energetic ions accelerated during laser-matter interactions. The optimization of the detector and of the advanced TOF methodology allow to obtain signals characterized by high signal-to-noise ratio and high dy...

Fusion energy research is delivering impressive new results emerging from different infrastructures and industrial devices evolving rapidly from ideas to proof-of-principle demonstration and aiming at the conceptual design of reactors for the production of electricity. A major milestone has recently been announced in laser fusion by the Lawrence Li...

We report on the development of a highly directional, narrow energy band, short time duration proton beam operating at high repetition rate. The protons are generated with an ultrashort-pulse laser interacting with a solid target and converted to a pencil-like narrow-band beam using a compact magnet-based energy selector. We experimentally demonstr...

Among the existing elemental characterization techniques, particle-induced x-ray emission (PIXE) and energy-dispersive x-ray (EDX) spectroscopy are two of the most widely used in different scientific and technological fields. Here, we present the first quantitative laser-driven PIXE and laser-driven EDX experimental investigation performed at the C...

We demonstrate laser-driven Helium ion acceleration with cut-off energies above 25 MeV and peaked ion number above $10^8$ /MeV for 22(2) MeV projectiles from near-critical density gas jet targets. We employed shock gas jet nozzles at the high-repetition-rate (HRR) VEGA-2 laser system with 3 J in pulses of 30 fs focused down to intensities in the ra...

We report on the development of a highly directional, narrow energy band, short time duration proton beam operating at high repetition rate, suitable for measurements of stopping power in high energy density plasmas as well as other applications. The protons are generated with an ultrashort-pulse laser interacting with a solid target and converted...

Among the existing elemental characterization techniques, Particle Induced X-ray Emission (PIXE) and Energy Dispersive X-ray (EDX) spectroscopy are two of the most widely used in different scientific and technological fields. Here we present the first quantitative laser-driven PIXE and laser-driven EDX experimental investigation performed at the Ce...

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

X-ray phase contrast imaging (XPCI) is more sensitive to density variations than X-ray absorption radiography, which is a crucial advantage when imaging weakly-absorbing, low-Z materials, or steep density gradients in matter under extreme conditions. Here, we describe the application of a polychromatic X-ray laser-plasma source (duration ~0.5 ps, p...

We present a scintillator-based detector able to measure the proton energy and the spatial distribution with a relatively simple design. It has been designed and built at the Spanish Center for Pulsed Lasers (CLPU) in Salamanca and tested in the proton accelerator at the Centro de Micro-Análisis de Materiales (CMAM) in Madrid. The detector is capab...

We present a scintillator-based detector able to measure the proton energy and the spatial distribution with a relatively simple design. It has been designed and built at the Spanish Center for Pulsed Lasers (CLPU) in Salamanca and tested in the proton accelerator at the Centro de Micro-Análisis de Materiales (CMAM) in Madrid. The detector is capab...

The double laser pulse approach to relativistic electron beam (REB) collimation in solid targets has been investigated at the LULI-ELFIE facility. In this scheme two collinear laser pulses are focused onto a solid target with a given intensity ratio and time delay to generate REBs. The magnetic field generated by the first laser-driven REB is used...

Efficient electron heating and enhanced ion acceleration by ultra-intense laser interaction with well-controlled near-critical plasmas were predicted numerically but remained relatively unexplored owing to the difficulty of creating such type of targets. We studied this regime on the CLPU VEGA-2 200 TW laser facility (6 J, 30 fs, at 10 21 W/cm 2) w...

Efficient electron heating and enhanced ion acceleration by ultra-intense laser interaction with well-controlled near-critical plasmas were predicted numerically but remained relatively unexplored owing to the difficulty of creating such type of targets. We studied this regime on the CLPU VEGA-2 200 TW laser facility (6 J, 30 fs, at 10 21 W/cm 2) w...

A prototype of a highly adjustable Kirkpatrick-Baez (KB) microscope has been designed, built, and tested in a number of laser driven x-ray experiments using the high power (200 TW) VEGA-2 laser system of the Spanish Centre for Pulsed Lasers (CLPU). The presented KB version consists of two, perpendicularly mounted, 500 μm thick silicon wafers, coate...

The double laser pulse approach to relativistic electron beam (REB) collimation has been investigated at the LULI-ELFIE facility. In this scheme, the magnetic field generated by the first laser-driven REB is used to guide a second delayed REB. We show how electron beam collimation can be controlled by properly adjusting laser parameters. By changin...

Ion stopping in dense plasmas plays a central role in Inertial Confinement Fusion (ICF) for the target self-heating by alpha-particles that triggers ignition and thermonuclear gain. It is crucial for target heating schemes using ion beams as main drivers like heavy-ion fusion or ion-driven fast ignition. Ion stopping in plasmas is also essential in...

The development of new diagnostics is important to improve the interpretation of experiments. Often well-known physical processes and techniques originally developed in unrelated fields of science can be applied to a different area with a significant impact on the quality of the produced data. X-ray phase-contrast imaging (XPCI) is one techniques w...

The Centro de Laseres Pulsados in Salamanca, Spain has recently started operation phase and the first user access period on the 6 J 30 fs 200 TW system (VEGA 2) already started at the beginning of 2018. In this paper we report on two commissioning experiments recently performed on the VEGA 2 system in preparation for the user campaign. VEGA 2 syste...

Laser–plasma interaction (LPI) at intensities $10^{15}{-}10^{16}~\text{W}\cdot \text{cm}^{-2}$ is dominated by parametric instabilities which can be responsible for a significant amount of non-collisional absorption and generate large fluxes of high-energy nonthermal electrons. Such a regime is of paramount importance for inertial confinement fusio...

Wavelength dependence of laser plasma interaction related to shock ignition approach – CORRIGENDUM - Volume 36 Issue 4 - T. Pisarczyk, S.Yu. Gus'kov, R. Dudzak, O. Renner, D. Batani, T. Chodukowski, Z. Rusiniak, J. Dostal, N.N. Demchenko, M. Rosinski, P. Parys, M. Smid, Ph. Korneev, E. Krousky, S. Borodziuk, J. Badziak, L. Antonelli, L.A. Gizzi, G....

This paper provides a summary of recent research connected with the shock ignition (SI) concept of the inertial confinement fusion which was carried out at PALS. In the experiments, Cu planar targets coated with a thin CH layer were used. Two-beam irradiation experiment was applied to investigate the effect of preliminary produced plasma to shock-w...

A promising prototype of a highly adjustable Kirkpatrick-Baez (KB) microscope has been designed, built and tested in a number of laser driven x-ray experiments using the high power (200TW) VEGA-2 laser system of the Spanish Centre for Pulsed Lasers (CLPU). The presented KB version consists of two, perpendicularly mounted, 500{\mu}m thick Silicon wa...

The Centro de Laseres Pulsados in Salamanca Spain has recently started operation phase and the first User access period on the 6 J 30 fs 200 TW system (VEGA 2) already started at the beginning of 2018. In this paper we report on two commissioning experiments recently performed on the VEGA 2 system in preparation for the user campaign. VEGA 2 system...

Laser wakefield acceleration (LWFA) can produce beams of energetic electrons in the range of a hundred of MeVs reaching, in some cases, the GeV regime . In addition the Betatron radiation generated by the transverse motion of the electrons in the LWFA represents nowadays a promising source of spatially coherent X-ray for a multiple direct applicati...

Warm dense matter (WDM, T~1-100 eV, ρ ~1-100 g/cm3) is encountered in numerous fields of research such as inertial confinement fusion, laboratory astrophysics or the modelling of planetary interiors. Numerous experiments have been carried out for generating and probing of WDM. The current experiment carried on at CLPU is concentrated on the measure...

Understanding the dynamics of rapidly varying electromagnetic fields in intense short pulse laser plasma interactions is of key importance to understand the mechanisms at the basis of a wide variety of physical processes, from high energy density physics and fusion science to the development of ultrafast laser plasma devices to control laser-genera...

We present the general challenges of plasma diagnostics for laser-produced plasmas and give a few more detailed examples: spherically bent crystals for X-ray imaging, velocity interferometers (VISAR) for shock studies, and proton radiography.

The reliability of Fricke gel dosimeters in form of layers for measurements aimed at the characterization of epithermal neutron beams has been studied. By means of dosimeters of different isotopic composition (standard, containing (10)B or prepared with heavy water) placed against the collimator exit, the spatial distribution of gamma and fast neut...

Recently a laser based Xray source has been developed in CLPU. This is the first based radioactive installation in Spain (License from the Spanish Nuclear Safety Council, IRA 3254). To generate the X-ray radiation, the laser is focalized on a metallic target (Copper) with intensities up to 10^16 W.cm^⁻2. At these intensities, electrons are extracte...

In an experiment at the laser facility ECLIPSE of the CELIA laboratory, University of Bordeaux, we measure the reflectivity of spherically bent crystals that are commonly used to investigate the propagation of fast electrons through the Kα radiation they generate in matter. The experimental reflectivity compares well with predictions from a ray-tra...

This paper reports on properties of a plasma formed by sequential action of two laser beams on a flat target, simulating the conditions of shock-ignited inertial confinement fusion target exposure. The experiments were performed using planar targets consisting of a massive copper (Cu) plate coated with a thin plastic (CH) layer, which was irradiate...

Energy loss in the transport of a beam of relativistic electrons in warm dense aluminum is measured in the regime of ultrahigh electron beam current density over 2 × 10 11 A=cm 2 (time averaged). The samples are heated by shock compression. Comparing to undriven cold solid targets, the roles of the different initial resistivity and of the transient...

Fricke-xylenol-orange gel has shown noticeable potentiality for in-phantom dosimetry in epithermal or thermal neutron fields with very high fluence rate, as those characteristic of nuclear research reactors. Fricke gels in form of layers give the possibility of achieving spatial distribution of gamma dose, fast neutron dose and dose due to charged...

Controlling the divergence of laser-driven fast electrons is compulsory to meet the ignition requirements in the fast ignition inertial fusion scheme. It was shown recently that using two consecutive laser pulses one can improve the electron-beam collimation. In this paper we propose an extension of this method by using a sequence of several laser...

Articles you may be interested in Combined x-ray scattering, radiography, and velocity interferometry/streaked optical pyrometry measurements of warm dense carbon using a novel technique of shock-and-releasea) Phys. Plasmas 21, 056309 (2014); 10.1063/1.4876613 High-energy, high-resolution x-ray imaging on the Trident short-pulse laser facilitya) Re...

Silver surfaces have been treated with plasma-enhanced chemical vapor deposition to produce SiO2-like coatings for possible applications in the jewelry industry. Different experimental conditions have been tested in order to optimize the protective effectiveness of the deposited layers. Samples were analyzed with optical and scanning electron micro...

The interaction of 40 ps pulse duration laser emitting at 532 nm wavelength with human dental tissue (enamel, dentin, and dentin–enamel junction) has been investigated. The crater profile and the surface morphology have been studied by using a confocal auto-fluorescence microscope (working in reflection mode) and a scanning electron microscope. Cra...

We present results on laser-driven relativistic electron beam propagation through aluminum samples, which are either solid and cold or compressed and heated by laser-induced shock. A full numerical description of fast electron generation and transport is found to reproduce the experimental absolute Kα yield and spot size measurements for varying ta...

Proton multiple scattering and nonrelativistic ion stopping in dense and hot plasma targets of ICF concern are cpnsidered as well as ion stopping in a strongly coupled and demixing binary ionic H-He mixture of planetary science interest

The ablation process of the tooth (enamel, dentin and dentin-enamel junction) by 40 ps laser pulses was investigated at 532 nm and 266 nm wavelengths. Fluorescence and scanning electron microscope (SEM) were used as diagnostics. The ablation threshold fluence was measured to be Fth similar to 5 J/cm(2) for enamel and for dentin. Ablation at 532 nm...

We studied the transport of an intense electron beam produced by high intensity laser pulses through metals and insulators. Targets were irradiated at two different intensities, 1017 W/cm2 and 1019 W/cm2, at the laser facility Xtreme Light XL-III in Beijing, a Ti:Sa laser source emitting 40 fs pulses at 800 nm. The main diagnostic was Cu-Kα fluores...

The relativistic laser-driven electron transport in partially or fully ionized matter has been investigated in many recent experiments. The high laser intensity achievable today (up to 1020 W/cm2) allows to generate electron current density above 1011 A/cm2. In this regime, electromagnetic effects start to be dominant over collisional ones. In this...

The PETAL system (PETawatt Aquitaine Laser) is a high-energy short-pulse laser, currently in an advanced construction phase, to be combined with the French Mega-Joule Laser (LMJ). In a first operational phase (beginning in 2015 and 2016) PETAL will provide 1 kJ in 1 ps and will be coupled to the first four LMJ quads. The ultimate performance goal t...

We present experimental and numerical results on intense-laser-pulse-produced fast electron beams transport through aluminum samples, either solid or compressed and heated by laser-induced planar shock propagation. Thanks to absolute K_{α} yield measurements and its very good agreement with results from numerical simulations, we quantify the collis...