15 Décembre – Thesis defense - Donaldi Mancelli
14 h Amphi B - Building A29
Generation of laser-driven shocks and their use to study simple compounds at high pressure.
Deep knowledge and understanding of the equation of state of simple materials such as the carbon and water in the warm dense matter (WDM) regime is essential for the modelling of the inner structure of many astrophysical objects, in particular Jovian planets as well as for inertial confinement fusion (ICF) research. Accurate equation of state data can be used to benchmark hydro codes and validate theoretical models such as SESAME, MPQEOS, FEOS and ab-initio equation of state calculated with density function theory (DFT) codes. The PHELiX at GSI Germany and GEKKO-XII at Institute of Laser Engineering ILE in Japan, laser facilities were used to drive planar shock waves in multi layered structured targets of diamond and water resulting in WDM conditions. We utilised a set of independent diagnostics to measure the thermodynamic conditions of WDM including velocity interferometry for any reflector (VISAR) and streaked optical pyrometry (SOP).This work presents a full set of measurements of the thermodynamic properties for different laser intensity drivers creating warm dense diamond and water. In addition to the laser compression work, results from experimental campaign using static compression on precompressed water samples with the use of diamond anvil cells are also being presented. The last part of thesis we will dedicate on theoretical Ab-initio work on LiH utilising Quantum Espresso code and CALYPSO for crystal structure prediction (CSP) at elevated pressures and three different formula units system, searching for intermediate candidate to explain the metal-insulator phase transition B1 − B2. Finally we present preliminary results from preparatory experimental campaign on high power and high repetition rate experiment for the L4n on P3 platform at ELI-Beamlines pointing out the challenges we have to face and the advances that will results from such laser facility.
