标题： 各向异性异常扩散和微重力尘埃等离子体中的非平衡性。 第二部分：谱分析 显示英文标题

标题： Anisotropic anomalous diffusion and nonequilibrium in microgravity dusty plasma. Part Two: Spectral Analysis

摘要： 在微重力尘埃等离子体中，各向异性异常尘埃扩散现象通过国际空间站上的Plasmakristall-4 (PK-4)设施的实验数据进行了研究。 PK-4实验使用摄像机跟踪单个尘埃粒子，从而可以收集大量关于尘埃粒子位置和速度的统计信息。 在本文的第一部分，这些统计信息被用来量化由PK-4中等离子体介导的尘埃-尘埃相互作用的各向异性引起的异常尘埃扩散。 在这里，我们使用标度关系将从数据中提取的统计参数转换为哈密顿谱模型的输入参数。 哈密顿的动能项（模拟异常扩散）由尘埃位移分布函数提供信息，而势能项（模拟随机性）由尘埃位置的波动提供信息。 研究每个哈密顿的能量状态谱以评估扩展态的概率（即谱的一个连续部分）。 谱模型显示，非局部性和随机性的结合导致希尔伯特空间中某些尺度上的传输具有高概率，这与实验中观察到的尘埃粒子跳跃特征空间尺度相吻合。 最后，我们讨论了这种谱方法如何推广到许多复杂系统，例如二维材料中的电子传输，其中统计模型不可行。 显示英文摘要

摘要： Anisotropic anomalous dust diffusion in microgravity dusty plasma is investigated using experimental data from the Plasmakristall-4 (PK-4) facility on board the International Space Station. The PK-4 experiment uses video cameras to track individual dust particles, which allows for the collection of large amounts of statistical information on the dust particle positions and velocities. In Part One of this paper, these statistics were used to quantify anomalous dust diffusion caused by anisotropies in the plasma-mediated dust-dust interactions in PK-4. Here we use scaling relations to convert statistical parameters extracted from data into input parameters for a Hamiltonian spectral model. The kinetic energy term of the Hamiltonian (modeling anomalous diffusion) is informed from the dust displacement distribution functions, while the potential energy term (modeling stochasticity) is informed from fluctuations in the dust positions. The spectrum of energy states for each Hamiltonian is studied to assess probability for extended states (i.e., a continuous portion of the spectrum). The spectral model shows that the combination of nonlocality and stochasticity leads to high probability for transport at certain scales in Hilbert space, which coincide with the characteristic spatial scales of dust particle jumps observed in the experiments. Lastly, we discuss how this spectral approach is generalizable to many complex systems, such as electron transport in 2D materials where statistical models are not feasible.