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

行星材料的导热系数是控制行星内部冷却速度和热演化的基本性质，因此也决定了行星的现代结构和内部动力学。然而，在相关的压力-温度条件下，候选材料在行星内部深处的热导率仍然很差，即在几千开尔文的Mbar压力范围之外。为了弥补这一知识空白，WWU明斯特矿物学研究所将采用超快泵浦探测光学技术和金刚石顶锤相结合的方法，建立新的热导率测量实验设备。然而，目前还没有独特的既定技术能够在感兴趣的广泛温度范围内测量晶格热导率，例如从小冰体内部的230K到岩石/冰(外)行星地幔的超过5000K。因此，基于时域热反射(TDTR)和闪光加热技术的两个子系统将被结合在一个独特的仪器中，目前在德国或国外的任何研究机构都无法获得。新仪器将是牵头工作组今后几十年研究活动的核心，并将促进地球科学和材料科学之间在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学性质的基本新数据，其中包括地幔硅酸盐和氧化物、铁合金、熔体和行星冰材料，以进一步限制行星核的导热系数、核-地幔边界的热通量或行星冰体的热演化等应用。此外，预计将与主办机构的材料科学小组合作，研究各种先进和功能材料的热通量。

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.