Laser-shock compression of silicon*

We performed laser-shock compression experiments on silicon. We directly observed the shock front traveling into the Si sample using a infrared velocity interferometer coupled to a visible system, and measured the Hugoniot equation-of-state up to 500 GPa. We found a significant disagreement in the Hugoniot between the present and previous data in the solid-liquid regime. We will also discuss the recent results on X-ray diffraction observation of shock-compressed Si in the solid-solid phase transformation regime.