First-principles equations of state and shock compression predictions of carbon- and boron-materials

Carbon- and boron-materials are important ablators in shock compression experiments for extreme physics and planetary studies. Accurate, wide-range equations of state (EOS) of these materials are crucial for interpreting the experiments and guiding the design of targets in inertial confinement fusion. In this talk, we present our latest results for a series of low-Z materials: CH, B, B₄C, and BN. We obtain coherent EOS by combining path integral Monte Carlo and quantum molecular dynamics simulations. We predict shock compression profiles to be compared with ongoing laser shock experiments on both conventional and gigabar platforms at NIF and OMEGA facilities. We compare with empirical EOS models based on Thomas-Fermi and Debye-Hückel theories. We study the compression maxima in detail and provide physical explanations of their origin by investigating the thermal and pressure-driven ionization processes. We also examine the sensitivity of the fusion yield to the ablator EOS in radiation-hydrodynamic simulations. These results from our first-principles simulations may be useful to benchmark future EOS calculations and offer means to systematically improve existing EOS models.