Single Shock Compression of Fluid Deuterium by QMC Simulation

Since liquid hydrogen has some complex physical behaviors in a relatively wide range of pressure and temperature, one more accurate and appropriate ab-initio simulation method is urgently required.We used the Coupled Electron-Ion Monte Carlo (CEIMC) method to simulate the single shock compression experiment of deuterium, and systematically studied its thermodynamic properties under high pressure.It is shown that the liquid deuterium principle Hugoniot has a maximum compression ratio of 4.48 at about 50.3 GPa, but the compression ratio does not increase gradually around 110 GPa.By utilizing an appropriate aluminum impedance match model, we have established the correlations between the states of compressed deuterium and the shock or particle velocities in aluminum taken before the shock wave crossing the Al-D₂ interface, and contemporarily summarized the physical processes of liquid deuterium under single shock compression in detail.The calculation results are not only in very good agreement with the existing experiments via different high-pressure generating technologies, but also consistent with the data above 100 GPa corrected from the Omega Laser driven experiment.Therefore, the CEIMC method combined with the wave function based on the resonant valence bond theory is very suitable for the simulations of shocked liquid deuterium.