Service des Photons Atomes et Molécules
Le SPAM est un Laboratoire de Recherche au sein de l'Iramis (Institut Rayonnement Matière de Saclay) rattaché à la Direction des Sciences de la Matière du CEA, dédié à la recherche fondamentale dans le domaine de l’interaction photons-matière et s’ouvrant également sur de nombreuses applications.
Le SPAM est membre du RTRA « Triangle de la Physique », du LABEX PALM et de l’IDEX Paris-Saclay. Le SPAM accueille une plateforme laser femtoseconde (SLIC) membre du réseau Européen LASERLAB et est impliqué dans 2 EQUIPEX : CILEX et ATTOLAB.
Les différents thèmes de recherche développés dans ses laboratoires sont présentés ci-après.
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Etude de la Matière sous Conditions Extrêmes |
Etudes sur les 'Serveurs Lasers Femto Seconde' |
Etude de la Dynamique Electronique Ultra-rapide en Champ Fort |
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Etude de la Physico Chimie d'Edifices Moléculaires |
Matière à Haute Densité d'Energie Etude de la physique des plasmas denses. |
#7 - Last update : 10/03 2022
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: The Physic at High Intensity (PHI) group of DSM/DRECAM studies the behaviour of solid density plasmas submitted to ultra-short (<60fs) and ultra-intense (1018-1019W/cm2) laser pulses. Following the recent progress concerning laser contrast improvement (2004), the interaction between a laser and a plasma at solid density is now possible.
Betatron radiation as a powerfull diagnostic for laser-plasma acceleration : Among the various parameters involved in laser-plasma acceleration mechanisms, the electrons themselves can be collected and studied. But, as they are collected at the end of the acceleration process, it is not trivial to get information about the “electron ‘s life”, from the trapping process up to the end of the acceleration one. During the acceleration phase, the electrons acquire relativistic energies and oscillate around the laser axis.
Brief introduction to ion acceleration : Undoubtedly, the acceleration of charged particles has been one of the most active research fields in the physics of laser-matter interaction all along the last ten years. In itself, laser driven ion acceleration was already a well known phenomenon although essentially circumscribed to the thermal expansion of the coronal plasma typical of nano and sub-nanosecond low intensities laser pulses interaction regimes.
ELISA (ELectron Injector for compact Staged high energy Accelerator) : ELISA (Electron Injector for High Energy Accelerator compact Staged): an electron injector for a multi-stage accelerator scheme (collaboration with LPGP University Paris-Sud / LULI-Ecole Polytechnique)
The ELISA project is to develop an experimentally controlled monoenergetic electron source, as an injector for a laser-plasma accelerator multi-stage (see Fig. 1).
Gallery :
February 2011
July 2010
Imaging XUV interferometer : Internal conversion frequency imaging interferometer at 32nm
Interferometry allows for getting electronic density information in 2D. For this purpose, we have set up, in collaboration with Attophysic group and LCF-IO, an innovative instrument based on the mutual coherence properties of two High order Harmonic (HHG) from gas jet in the XUV domain. Interferometry, in this wavelength domain, exhibits strong difficulties, due to handling of the beams.
In progess... : En cours de rédaction...
Work in progess...
Influence of the temporal evolution of the plasma on the laser pulse propagation : We have performed numerical simulations with the 2D PIC code CALDER (coll. Erik Lefebvre – CEA-DAM BIII) to understand the temporal evolution of the high intensity ultra-short laser pulse into the plasma. First, we have tested the code by simulating the propagation of the laser in conditions relevant to an experiment performed by collaborators from Pisa University and we succeeded to described and interpret part of their experimental results.
Members of MHDE group : Permanent researchers :
Thomas Blenski
+33 1 69 08 96 64
thomas.blenski@cea.fr
Theory: physic of dense plasmas
Michel Poirier
+33 1 69 08 46 29
michel.poirier@cea.fr
Theory: atomic physic
Frédéric Thais
+33 1 69 08 15 73
frederic.thais@cea.fr
Experiences on high energy lasers and interpretation
PhD students :
Robin Piron
+33 1 69 08 65 14
robin.piron@cea.
Modeling DNA excitons : Modeling DNA excitons
We have modeled the Franck-Condon excited states of DNA duplexes and G-quadruplexes. Our calculations were performed in the frame of the exciton theory combining molecular dynamics simulations (collaboration with Richard Lavery and Krystyna Zakrzewska) and data from quantum chemistry (atomic transition charges for the calculation of dipolar coupling).
MRI constrast agents : The solvation dynamics of complexed metal cations, like liganded gadolinium Gd(III), used as contrast agents in Magnetic resonance Imaging, controls the contrast observed in the MRI images. In this context, the simulation at the molecular level of the dynamical behavior of these species and of their environment (in solution) is crucial for the understanding of the phenomena involved.
Perspectives : Next steps in research on laser driven ion acceleration in Saclay
Relying on a rich set of human resources, technical expertise and equipment, we are going to implement an ambitious program of research.
a) Energy scaling laws
Most of the existing models wich are supposed to give scaling laws about proton beams main features (maximum energy, number of accelerated particles) seem better suited to high-energy and "long" duration (~ ps) laser pulses.
Ph.D opportunities : Attophysic group
Ultrafast nanoscale imaging using XUV coherent diffraction (see more ...)
Generation and applications of attosecond pulses (see more ...)
Femtosecond photoelectron diffraction imaging using few-cycle laser pulses (see more ...)
PHI group
Fast ion generation in the ultra-relativistic regime and applications (see more ...
Plasma diagnostic : .....................
Publications MHDE : Groupe "2006","2006"
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Publications PHI : Groupe"2006","2006" 200600005314 200600005998 -----------------
Reflectivity measurement in the XUV domain : Spectrally and temporally resolved reflectivity measurement for studying the temporal evolution of a dense plasma of interest for the Warm Dense Matter problematic...
The properties of Warm Dense Matter ( WDM - solid density and temperature of several eV's ) are a subject of strong interest among a wide scientist community ranging from astrophysicists to solid-state physicists.
Transmission measurement in the XUV domain : Temporal evolution of XUV transmission with 100fs resolution for characterizing plasmas created by intense irradiation of thin polypropylene foils.
The plasma is created by intense irradiation (I≈3x1017W/cm2) of thin polypropylene foils, on UHI10 laser facility (CEA-Saclay). The pedestal, which could damages the target before the arrival of the intense part of the laser pulse, has been reduced implementing plasma mirror on the laser system.
