Pump-probe optical setup for thermal conductivity measurements in planetary materials

行星材料的导热性是一个基本性质，它决定着行星内部的冷却速率和热演化，因此也决定着它们现在的结构和内部动力学。然而，在相关的压力-温度条件下，即在几千开尔文的Mbar压力范围之外，行星内部深处候选材料的热导率仍然受到很大的限制。为了解决这一知识差距，将在WWU Münster矿物学研究所实施新的实验设施，用于采用超快泵浦探测光学技术与金刚石砧室相结合的热导率测量。 然而，目前还没有一种独特的成熟技术能够在感兴趣的广泛温度范围内进行晶格热导率测量，例如从小型冰体内部的230 K到岩石/冰（外）行星地幔中的5000 K以上。因此，基于时域热反射（TDTR）和闪速加热技术的两个子系统将结合在一个独特的仪器中，该仪器目前在德国或国外的任何研究机构都不可用。新的仪器将是牵头工作组今后几十年研究活动的核心，并将促进地球科学与材料科学之间前沿领域的跨学科合作。该仪器的目的是提供关于各种相关化合物的热特性的基本新数据，包括地幔硅酸盐和氧化物、铁合金、熔体和行星结冰材料，以进一步限制行星核的热导率、核幔边界的热通量或行星结冰体的热演化等应用。此外，预计将与东道机构的材料科学小组合作，应用于调查各种先进和功能材料中的热通量。

The thermal conductivity of planetary materials is a fundamental property that governs the cooling rates and thermal evolution of planetary interiors and hence, their present-day structure and internal dynamics. Yet, the thermal conductivity of candidate materials in deep planetary interiors remains poorly constrained at relevant pressure-temperature conditions, i.e. beyond the Mbar pressure range at several thousand Kelvin. To address this gap in knowledge, new experimental facilities for thermal conductivity measurements applying ultrafast pump-probe optical techniques coupled with diamond anvil cells will be implemented at the Institute of Mineralogy of WWU Münster. At present, however, there is no unique established technique that enables lattice thermal conductivity measurements over the broad range of temperatures of interest, e.g. from 230 K in the interior of small icy bodies to beyond 5000 K in the mantle of rocky/icy (exo)planets. Therefore, two sub-systems based on the Time-domain thermo-reflectance (TDTR) and flash heating techniques will be combined in a unique instrument currently not available at any research institution within Germany or abroad. The new instrument will be central in the research activities of the lead working group for the next decades and will promote interdisciplinary collaborations at the frontiers between geosciences and material sciences. The instrument is intended to provide fundamental new data on the thermal properties of a variety of relevant compounds, including mantle silicates and oxides, iron alloys, melts and planetary icy materials, to further constrain the thermal conductivity of planetary cores, the heat fluxes at the core-mantle-boundary or the thermal evolution of planetary icy bodies, among other applications. In addition, applications to investigate the thermal fluxes in a variety of advanced and functional materials are foreseen in collaboration with material sciences groups at the host institution.