Understanding the Physics of Shock and Release in ICF Targets by Large-scale Molecular Dynamics Simulations

Large-scale molecular dynamics (MD) offers a powerful tool to simulate a variety of high-energy-density problems, such as phase transformation, chemical dissociation and recombination, and their kinetics along various and controlled thermodynamic paths. This technique has extremely fine resolution in the level of atoms. This offers the capability to study detailed motion of every species of materials in inertial confinement fusion (ICF) experiments that is challenging to the often-used hydrodynamic simulation methods. Following our pioneering MD simulations on CH and CH-DT shock release in the past several years, we have further performed simulations of shock release in a DT ice-gas system, compare MD predictions on CH-DT shock release against single-fluid hydrodynamic simulations, and show MD results based on bond-order versus machine-learning force fields. This talk aims to report new findings based on the computational work, build a general theoretical framework of materials shock release physics to be benchmarked by experiments on the Omega laser facilities, and eventually help understand the performance and improve the design of ICF targets.