This work presents studies which demonstrate the importance of the very early heating dynamics of the ablator long before the ablation plasma phase begins in laser driven inertial confinement fusion (ICF) studies. For the direct-drive fusion concept using lasers, the development of perturbations during the thermo-elasto-plastic (TEP) and melting phases of the interaction of the laser pulse with the ablator's surface may act as seeding to the subsequent growth of hydro-dynamic instabilities apparent during the acceleration phase of the interaction such as for instance the Rayleigh–Taylor and the Richtmyer–Meshkov, which strongly affect the implosion dynamics of the compression phase. The multiphysics-multiphase finite-element method (FEM) simulation results are experimentally validated by advanced three-dimensional whole-field dynamic imaging of the surface of the ablator allowing for a transverse to the surface spatial resolution of only approximately 1 nm. The study shows that the TEP and melting phases of the interaction are of crucial importance since transverse perturbations of the ablator's surface can reach tens of nanometres in amplitude within the TEP and melting phases. Such perturbations are of Rayleigh type and are transferred from the ablator to the substrate from the very first moments of the interaction. This article is part of a discussion meeting issue ‘Prospects for high gain inertial fusion energy (part 1)’.

中文翻译：

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在惯性约束聚变研究中烧蚀等离子体阶段之前的激光脉冲-烧蚀器相互作用动力学的重要性

这项工作提出了一些研究，这些研究证明了在激光驱动惯性约束聚变 (ICF) 研究中，在消融等离子体阶段开始之前很久，消融器的早期加热动力学的重要性。对于使用激光的直接驱动聚变概念，热弹塑性 (TEP) 和激光脉冲与烧蚀器表面相互作用的熔化阶段的扰动的发展可能作为随后流体动力增长的种子。在相互作用的加速阶段存在明显的不稳定性，例如 Rayleigh-Taylor 和 Richtmyer-Meshkov，它们强烈影响压缩阶段的内爆动力学。多物理场-多相有限元法 (FEM) 仿真结果通过烧蚀器表面的先进三维全场动态成像进行实验验证，允许横向于表面的空间分辨率仅为大约 1 nm。研究表明，相互作用的 TEP 和熔化阶段至关重要，因为在 TEP 和熔化阶段内，烧蚀器表面的横向扰动的幅度可以达到数十纳米。这种扰动是瑞利类型的，并且从相互作用的最初时刻就从消融器转移到基板上。本文是讨论会议问题“高增益惯性聚变能的前景（第 1 部分）”的一部分。