Stage - Bac+4 - +5 - Etude Numérique de l'Endommagement Laser de la Silice H/F CEA

The CEA-CESTA hosts the Laser MegaJoule (LMJ), a high energy laser facility dedicated to studying matter under extreme conditions of temperature and pressure. The LMJ facility consists of 176 laser beams which each of them is build with near 40 optical components. The resistance of these components to laser flux is critical to the proper functioning of the LMJ.
The laser optical components are dielectric materials, which, as long as the laser energy density remains below a ionization threshold, are transparent. It has been experimentally observed that, above this threshold, a damage manifests in the component on a local scale, which consequently results in a modification of its optical properties. This may result in the replacement of the component. As the laser intensity is increased, the electrons in the valence band will undergo ionization, thereby creating an area where the laser energy will be absorbed. The transfer of this energy to the lattice can result in a change in the material, the extent of which is contingent upon the rate of laser energy absorbed. The internship will entail an examination of this initial stage of laser damage processes occurring inside a fused silica target as it is irradiated by a high-energy laser beam. A series of simulations will be conducted to investigate the propagation of laser pulses within fused silica. These simulations will employ the ARCTIC code, a highly parallelized three-dimensional numerical code designed specifically for the simulation of laser pulse propagation in dielectric materials. A particular emphasis will be placed on the posterior aspect of the target, which has been demonstrated through experimental means to be a primary site for damage.
The internship will be localized in CEA-CESTA, 33116 Le Barp. The student will have access to the transport services provided by the CEA-CESTA

Conformément aux engagements pris par le CEA en faveur de l'intégration des personnes handicapées, cet emploi est ouvert à toutes et à tous. Le CEA propose des aménagements et/ou des possibilités d'organisation pour l'inclusion des travailleurs handicapés.
Participant à la protection nationale, une enquête administrative est réalisée pour tous les collaborateurs du CEA afin d'assurer l'intégrité et la sécurité de la nation.