The long-time diffusion of two-dimensional dusty plasmas on a one-dimensional periodic substrate with varied widths is investigated using Langevin dynamical simulations. When the substrate is narrow and the dust particles form a single row, the diffusion is the smallest in both directions. We find that as the substrate width gradually increases to twice its initial value, the long-time diffusion of the two-dimensional dusty plasmas first increases, then decreases, and finally increases again, giving an oscillation-like diffusion with varied substrate width. When the width increases to a specific value, the dust particles within each potential well arrange themselves in a stable zigzag pattern, greatly reducing the diffusion, and leading to the observed oscillation in the diffusion with the increasing width. In addition, the long-time oscillation-like diffusion is consistent with the number of dust particles that are hopping across the potential wells of the substrate.
Experimental observation of strong coupling effects on the dispersion of dust acoustic waves in a plasma
实验研究了高岭土和$MnO_2$尘埃颗粒混合物在氩等离子体中的低频尘埃声波在强耦合区的色散特性。中性压力在一个很宽的范围内变化，以改变尘埃等离子体的碰撞性质。在低碰撞制度的营业额的色散曲线在较高的波数和由此产生的区域的$\partialω/\partial k < 0$被确定为签名的尘埃尘埃相关性。在高碰撞制度尘埃中性碰撞产生类似的效果，并防止明确识别强耦合效应。
Effect of size and shape of a moving charged object on the propagation characteristics of precursor solitons
我们报告的实验观测的修改的前体孤子的传播特性，由于不同的形状和大小的对象，尘埃流体的流动。实验已经在$Π$形状的尘埃等离子体实验（DPEx）装置中进行，其中尘埃等离子体在DC辉光放电Ar等离子体中使用高岭土颗粒产生。在阴极上径向安装的浮动铜线在等离子体环境中充当带电物体。粉尘流体上的流动是通过将带电物体的电位从接地电位突然降低到接近浮动电位而启动的。电位山的大小（高度和宽度）通过一个可变电阻从导线中引出电流而改变。随着势峰高度的减小，孤子的振幅、速度和数目减小，而孤子的宽度增大.结果发现，低于阈值，这些孤立波不激发和尘埃流体简单地流过山。为了检查由于电势分布的形状引起的效果，用三角形物体代替导线。只有拖尾尾流被认为是激发时，尘埃流体面临的线性增加的斜率的潜在的配置文件，而孤立子和唤醒得到激发时，对象被放置与尖锐的边缘面对流。所有的实验结果定性同意与不同的源项在强迫Korteweg de Vries（f-KdV）模型方程的数值解。
