Collective motion of macroscopic spheres floating on capillary ripples: dynamic heterogeneity and dynamic criticality.
Collective motion of macroscopic spheres floating on capillary ripples: dynamic heterogeneity and dynamic criticality.
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漂浮在毛细管波纹上的宏观球体的集体运动：动态异质性和动态临界性。
DOI：
10.1103/physreve.90.033018
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
D. van der Meer
中科院分区：
文献类型：
--
作者：
Ceyda Sanli;Kuniyasu Saitoh;S. Luding;D. van der Meer
当一个密集的单层宏观球漂浮在混乱的毛细法拉第波，大规模的对流运动和笼动力学的玻璃系统的典型共存观察。我们减去对流平均流量使用粗粒化（均匀化）的方法，并揭示subdiffusion的笼子里的时间尺度，随后在以后的时间扩散制度。我们应用开发的方法来研究动态异质性，并表明，典型的时间和长度尺度的波动，由于观察到的颗粒群的重排显着增加时，系统接近其最大的实验可访问的包装浓度。为了将系统连接到动态临界文献，我们将幂律拟合到我们的结果。由此产生的临界指数是一致的，发现在密集的胶体悬浮液。
When a densely packed monolayer of macroscopic spheres floats on chaotic capillary Faraday waves, a coexistence of large scale convective motion and caging dynamics typical for glassy systems is observed. We subtract the convective mean flow using a coarse graining (homogenization) method and reveal subdiffusion for the caging time scales followed by a diffusive regime at later times. We apply the methods developed to study dynamic heterogeneity and show that the typical time and length scales of the fluctuations due to rearrangements of observed particle groups significantly increase when the system approaches its largest experimentally accessible packing concentration. To connect the system to the dynamic criticality literature, we fit power laws to our results. The resultant critical exponents are consistent with those found in densely packed suspensions of colloids.