Large Scale Quantum Simulations Plasmas

原则上，等离子体中的电子是量子物体。除了在高温和低密度的情况下，电子的量子性质不起重要作用，我们需要考虑它。其中一个典型的例子是惯性约束聚变中离子和电子强耦合的内爆过程，由于晶格的长程有序性的缺乏，使得量子等离子体的理论处理变得困难，数值模拟成为一种重要的分析方法。量子模拟通常需要大量的计算资源，并且适用的系统规模有限。除此之外，我们还有另一个困难来自库仑相互作用的长程性质。本研究的目的就是要解决这些问题，我们应用密度泛函分子动力学（DFMD）来克服2中的第一点。该方法将电子密度作为一个动态变量 关于我们 并且可以进行大规模的量子模拟。我们已经分析了氢等离子体在液态金属领域，并表明，量子模拟与1000个电子是负担得起的。我们还证实，通过采用并行PC集群，我们可以模拟比后者大一到两个数量级的系统。为了解决第二个问题，我们开发了基于快速多极子方法（FMM）的计算程序。我们已经应用我们的代码库仑集团，并发现其结构相变的临界系统尺寸。我们还将我们的代码Yukawa系统，可以被视为量子等离子体中的离子的最简单的近似。汤川系统作为一个模型的尘埃等离子体的行为是一个重要的课题，在等离子体处理。应用于Yukawa系统不仅为我们提供了一个参考系统，而且为真实的系统提供了有用的结果。少

In principle, electrons in plasmas are quantum objects. Except for the cases at high temperatures and with low densities where the quantum nature of electrons does not play an important role, we need to take it into account. One of typical examples is the implosion process in the inertial confinement fusion where ions and elecrons are strongly coupled.The lack of long-range order of crystalline lattice makes theoretical treatment of quantum plasmas difficult and numerical simulations become an important method of analysis. The quantum simulation usually requires large computational resources and the applicable system size is limited. In addition to this, we have another difficulty coming from the long-range nature of the Coulomb interaction. The purpose of this research project is to find solutions for these problems.We have applied the density functional molecular dynamics (DFMD) to overcome the first point in 2. In this method, the electron density is regard ed as a dynamic variable … More and one can perform large scale quantum simulations. We have analyzed the hydrogen plasma in the domain of liquid metal and have shown that quantum simulations with 1000 electrons are affordable. We have also confirmed that, by employing parallel PC clusters, we can simulate systems larger than the latter by one or two orders of magnitude. We have also checked the accuracy of DFMD by comparing the results with those of first principle simulations.To solve the second problem in 2, we have developed the computation code on the basis of the Fast Multipole method(FMM). We have applied our code to Coulomb clusters and found the critical system size for its structural phase transition. We have also applied our code to the Yukawa system which can be regarded as the simplest approximation for ions in quantum plasmas. The Yukawa system serves as a model of dusty plasmas whose behavior is an important subject in relation to plasma processing. Applications to Yukawa systems provide us with not only a reference system but also useful results for real systems. Less