强冲击压缩下LiF，Al2O3和LiTaO3单晶的透光性

在二级轻气炮上，用高速电子相机扫描照相技术和改进的Mallory实验装置，对z切LiF，Al₂O₃(蓝宝石)和LiTaO₃单晶材料的冲击透光性进行了对比测量，并用黑密度计提取出动态图像定量化的光强对比度变化曲线.结果表明，LiF单晶在102 GPa压强下能够保持长时间的初始透光性不变，与公认的LiF具有优良的高压下透明性的认识一致.LiTaO₃单晶在实验压力(139GPa)下变成基本不透明.而Al_{关键词： 2}O₃')" href="#">Al₂O₃ LiF 3')" href="#">LiTaO₃ 光学透明性

Optical transparency of z-cut LiF, Al2O3 and LiTaO3 single crystals under strong shock compression

In this paper, a comparative experimental study on optical transparency of z-cut LiF, sapphire and LiTaO₃ under 10¹¹ Pa shock compression at our two-stage light-gas gun facility is presented. In our experiments, intensity contrast variation of light emitted from a modified experimental setup of Mallory-type was monitored by a high-speed electronic camera. The results demonstrated that the LiF under the shock pressure of 102 GPa retains its initial transparency in the whole observation time interval, which is in good agreement with the common view of good sustained transparency of LiF. The LiTaO₃ became basically opaque at 139 GPa. Sapphire at 131 GPa shock pressure showed a continuous transparency degradation till became completely darkened when the shock wave was arriving at the free-surface.