Laser generated shock reflectance data show that diamond undergoes a continuous transition from optically absorbing to reflecting between Hugoniot pressures 600<PH<1000 GPa. The data are consistent with diamond having a thermal population of carriers at PH̃600 GPa, undergoing band overlap metallization at PH̃1000 GPa and melting at 800<PH<1000 GPa. The results agree well with an equation of state model that predicts that elemental carbon remains solid throughout the interior of Neptune.
Physical Review Letters
- Pub Date:
- November 2004
- High-pressure and shock wave effects in solids and liquids;
- Solid-liquid transitions;
- Metal-insulator transitions and other electronic transitions