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arXiv 1809.02473physics.plasm-phphysics.comp-ph
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等离子体-固体界面的综合模拟

Towards an integrated modeling of the plasma-solid interface

M Bonitz, A Filinov, J W Abraham, K Balzer, H Kählert, E Pehlke, FX Bronold, M Pamperin, M M Becker, D Loffhagen, H Fehske

摘要:

固体面对等离子体是许多天体物理系统和实验室设置中的常见情况。此外,许多等离子体技术应用依赖于等离子体-表面相互作用的控制。然而,目前往往缺乏对它们的基本理解,因此大多数技术应用都是通过试错来开发的。在大多数的等离子体模拟表面过程被忽略或处理通过现象学参数,如粘附系数,溅射率或次级电子发射系数。然而,这些参数仅在某些情况下是已知的,并且精确度非常有限。同样,虽然表面物理模拟经常研究单个离子或中性粒子的影响,但到目前为止,等离子体介质的影响和连续撞击之间的相关性尚未考虑在内。这种方法不可能有预测能力。在本文中,我们讨论了一些详细的物理过程的等离子体-固体界面,使我们的必要性耦合等离子体-固体模拟。我们简要地总结了相关的理论方法,从固态和表面物理,是适合于这种方法作出贡献,并确定四种方法。第一种是介观模拟,如动力学蒙特卡罗(KMC)和分子动力学(MD),能够处理大尺度上的复杂过程,但忽略了电子效应。第二种是基于量子玻尔兹曼方程的量子动力学方法,该方法使用简化的固体模型来更准确地处理表面过程。第三种方法是基于密度泛函理论和含时密度泛函理论的表面过程从头计算模拟。第四类是非平衡格林函数,能够处理材料中和界面处的关联效应。

英文摘要:

Solids facing a plasma are a common situation in many astrophysical systems and laboratory setups. Moreover, many plasma technology applications rely on the control of the plasma-surface interaction. However, presently often a fundamental understanding of them is missing, so most technological applications are being developed via trial and error. In the majority of plasma simulations surface processes are either neglected or treated via phenomenological parameters such as sticking coefficients, sputter rates or secondary electron emission coefficients. However, those parameters are known only in some cases and with very limited accuracy. Similarly, while surface physics simulations have often studied the impact of single ions or neutrals, so far, the influence of a plasma medium and correlations between successive impacts have not been taken into account. Such an approach cannot have predictive power. In this paper we discuss in some detail the physical processes a the plasma-solid interface which brings us to the necessity of coupled plasma-solid simulations. We briefly summarize relevant theoretical methods from solid state and surface physics that are suitable to contribute to such an approach and identify four methods. The first are mesoscopic simulations such as kinetic Monte Carlo (KMC) and molecular dynamics (MD) that are able to treat complex processes on large scales but neglect electronic effects. The second are quantum kinetic methods based on the quantum Boltzmann equation that give access to a more accurate treatment of surface processes using simplifying models for the solid. The third approach are ab initio simulations of surface process that are based on density functional theory (DFT) and time-dependent DFT. The fourths are nonequilibrium Green functions that able to treat correlation effects in the material and at the interface.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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