Development of an Ultrafast Laser Instrument for Probing Earth and Planetary Materials under Extreme Pressures and Temperatures

地球和行星材料的弹性知识是解释地震异常和评估地球的必要条件。而它们的输运性质（热导率和电导率）是控制地核和地幔热历史及其动力学的关键参数。这些性质与行星的吸积和分异、地幔和地核温度的时间演化以及地球的形成有关。S磁场。尽管最近有了许多技术发展，但在极端条件下对上述材料性能的原位测量仍然是一个具有挑战性的问题。该项目将开发新的、快速的、基于激光的仪器，用于在金刚石砧细胞（DAC）中承受极高压力和温度（P-T）的材料的弹性和传输特性（热和能量依赖的光学导电性）的原位测量。该项目团队将采用现有的声学干涉测量（AI）和时域热反射（TDTR）技术，用于该研究小组开发的脉冲激光加热DAC技术。他们将设计并建造一个宽带光谱（BBOS）装置，该装置将允许使用超亮脉冲fs激光源在高P-T条件下从紫外到中红外的材料光学特性的原位测量。

Knowledge of elasticity of Earth and planetary materials is needed for interpretation of the seismic anomalies, evaluation of the Earth?s and other planets compositional and dynamical models, while their transport properties (thermal and electrical conductivity) are the key parameters controlling the thermal history of the core and mantle and their dynamics. These properties are related to the planetary accretion and differentiation, the time evolution of mantle and core temperatures, and the generation of the Earth?s magnetic field. In spite of numerous recent technical developments, in situ measurements of the above listed materials properties under extreme conditions remain a challenging problem. This project will develop new, fast, fs laser-based instrumentation for in situ measurements of elasticity and transport properties (thermal and energy dependent optical conductivity) of materials subjected to extreme high pressure and temperature (P-T) in the diamond anvil cell (DAC). The project team will adapt the existing acoustic interferometry (AI) and time-domain thermoreflectance (TDTR) techniques for the pulsed laser heated DAC technology developed by this research group. They will design and build a broadband spectroscopy (BBOS) setup, which will allow in situ measurement of material optical properties at high P-T conditions from ultraviolet to mid infrared using an ultra-bright pulsed fs laser source.