论文标题
在拥挤的活动系统的晶格模型中增强了示踪粒子的扩散
Enhanced diffusion of a tracer particle in a lattice model of a crowded active system
论文作者
论文摘要
亚细胞，细胞和多细胞水平的生活系统通常是包含活性颗粒的拥挤系统。这些颗粒的主动运动也可以推动被动颗粒，这通常会导致被动颗粒的有效扩散增强。在这里，我们研究了一种被动示踪剂粒子在如此致密的人群系统中的扩散，使用了一个最小的晶格模型，这些晶格模型融合了彼此推动的颗粒。我们表明该模型表现出多种运动状态，并量化了活跃人群密度和活性的增强扩散。此外，我们展示了示踪剂扩散和活动颗粒聚类的相互作用，从而抑制了增强的扩散。被动和主动人群混合物的模拟表明，仅有一小部分的活性颗粒就足以观察增强的扩散。
Living systems at the sub-cellular, cellular, and multi-cellular level are often crowded systems that contain active particles. The active motion of these particles can also propel passive particles, which typically results in enhanced effective diffusion of the passive particles. Here we study the diffusion of a passive tracer particle in such a dense system of active crowders using a minimal lattice model incorporating particles pushing each other. We show that the model exhibits several regimes of motility and quantify the enhanced diffusion as a function of density and activity of the active crowders. Moreover, we demonstrate an interplay of tracer diffusion and clustering of active particles, which suppresses the enhanced diffusion. Simulations of mixtures of passive and active crowders show that a rather small fraction of active particles is sufficient for the observation of enhanced diffusion.
