Sound Velocity Measurement of Shock-Compressed Quartz at Extreme Conditions

Abstract

The physical properties of basic minerals such as magnesium silicates, oxides, and silica at extreme conditions, up to 1000 s of GPa, are crucial to understand the behaviors of magma oceans and melting in Super-Earths discovered to data. Their sound velocity at the conditions relevant to the Super-Earth’s mantle is a key parameter for melting process in determining the physical and chemical evolution of planetary interiors. In this article, we used laser indirectly driven shock compression for quartz to document the sound velocity of quartz at pressures of 270 GPa to 870 GPa during lateral unloadings in a high-power laser facility in China. These measurements demonstrate and improve the technique proposed by Li et al. [PRL 120, 215703 (2018)] to determine the sound velocity. The results compare favorably to the SESAME EoS table and previous data. The Grüneisen parameter at extreme conditions was also calculated from sound velocity data. The data presented in our experiment also provide new information on sound velocity to support the dissociation and metallization for liquid quartz at extreme conditions.

Shock compression of coesite up to 950 GPa

“…The Grüneisen parameters identified by the Cst-Qz Hugoniot pair decrease monotonically with decreasing volume and are markedly larger than those determined by Qz-Stv or Cst-Stv Hugoniot pairs, [Luo et al, 2002a] but it is comparable with the previous values derived from continuous sound velocity of shocked Qz and those by DFT-MD simulations. [Li et al, 2018;Sun et al, 2021] The discrepancy of γ from the Cst-Qz Hugoniot pair and Cst-Stv Hugoniot pair is due to the highorder anharmonic effect of temperature. The temperatures at 550 GPa are 2.5×10 4 K for quartz but only 8300 K for stishovite.…”

“…[Hicks et al, 2006;Millot et al, 2015] Such a large temperature difference at a given volume will result in underestimation of γ. Luo et al, 2002a;Sun et al, 2021;Wang et al, 2012] The subscripts indicate methods: a pair of two Hugoniots from different phases, b sound velocity, c simulations by DFTMD, d thermodynamic derivative, and e static compression data by DAC.…”

“…Additional data for discussion in Figure 3 are sourced from Hicks et al, (2006); Lyzenga et al, (1983); Millot et al, (2015); Andrault et al, (2020); Usui and Tsuchiya, (2010); Duffy et al, (2015); Fischer et al, (2018). Additional data for discussion in Figure 4 are sourced from Li et al, (2018); Luo et al, (2002a);; Sun et al, (2021); Wang et al (2012). Additional data for discussion in Figure 5 are sourced from Brygoo et al, (2015); Millot et al, (2015); Guarguaglini et al, (2021); Hicks et al, (2006); Mazevet et al, (2015); Scipioni et al, (2017).…”

“…γ was deduced from the P-V Hugoniot relations of quartz (Qz), coesite (Cst) and stishovite (Stv) by the Mie-Grüneisen equation of state in this study, and plotted together with previous data. [LiLuo et al, 2002a;Sun et al, 2021;Wang et al, 2012] The subscripts indicate methods:a pair of two Hugoniots from different phases, b sound velocity, c simulations by DFTMD, d thermodynamic derivative, and e static compression data by DAC.…”