Dynamic Clustering and Chemotactic Collapse of Self-Phoretic Active Particles
Dynamic Clustering and Chemotactic Collapse of Self-Phoretic Active Particles
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DOI：
10.1103/physrevlett.112.238303
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发表时间：
2014-06-10
影响因子：
8.6
通讯作者：
Stark, Holger
中科院分区：
文献类型：
--
作者：
Pohl, Oliver;Stark, Holger
最近的低浓度自泳粒子实验显示出明显的动态聚类[I. Theurkauff 等人，物理学。莱特牧师。 108, 268303 (2012)]。我们通过考虑活性粒子在其自生化学场中执行的平移和旋转扩散电泳运动来模拟这种情况。仅当这两种泳动贡献分别引起竞争性吸引和排斥相互作用时，我们的布朗动力学模拟才显示出明显的动态聚类。我们确定了两种动态聚类状态，并通过幂律指数分布来表征它们。在仅仅吸引的情况下，趋化崩溃直接从气体状态发生到崩溃状态，我们还通过将朗之万动力学映射到细菌趋化的凯勒-西格尔模型上来预测这一点。
Recent experiments with self-phoretic particles at low concentrations show a pronounced dynamic clustering [I. Theurkauff et al., Phys. Rev. Lett. 108, 268303 (2012)]. We model this situation by taking into account the translational and rotational diffusiophoretic motion, which the active particles perform in their self-generated chemical field. Our Brownian dynamics simulations show pronounced dynamic clustering only when these two phoretic contributions give rise to competing attractive and repulsive interactions, respectively. We identify two dynamic clustering states and characterize them by power-law-exponential distributions. In case of mere attraction a chemotactic collapse occurs directly from the gaslike into the collapsed state, which we also predict by mapping our Langevin dynamics on the Keller-Segel model for bacterial chemotaxis.