Development of in-situ high-pressure and -temperature chemical analysis technique by femto-second laser-induced breakdown spectroscopy

板坯衍生的流体可以含有大量的硅酸盐成分，但这种流体很难淬火，其组成也不能准确确定。在这项研究中，我提出了一种新的高压高温条件下流体化学分析的现场方法。在这种方法中，脉冲激光聚焦在金刚石顶压室(DAC)内的小面积样品中。将产生等离子体，然后等离子体冷却形成中性原子。然后，原子固有的特征波长光将被发射出来。通过对光的分析，我们可以确定DAC中流体的化学成分。为了评价该方法，引入了外热式DAC、单色仪、门控增强器和CCD探测器以及皮秒激光，到目前为止，已经使用外热式DAC产生了高压和高温流体，但还没有检测到DAC中的激光诱导等离子体光。

Slab-derived fluids can contain substantial amounts of silicate components, but it is difficult to quench such fluids, and its composition can not be determined precisely. In this study, I proposed a novel in-situ method for chemical analysis of fluid under high pressure and temperature conditions. In this method, pulsed laser beam is focused in small area of sample within diamond anvil cell (DAC). Plasma will be produced, and then plasma cools down to form neutral atoms. Then characteristic wavelength light inherent to atoms will be emitted. By analyzing this light, we can determine chemical composition of the fluid in DAC.To evaluate this proposed method, externally-heated DAC, monochrometer, gated-intensifier and CCD detector, and pico-second laser are introduced, So far, high-pressure and temperature fluids have been produced using externally heated DAC, but laser induced plasma light in DAC has not been detected yet.