Emergence of Bimodal Motility in Active Droplets
Emergence of Bimodal Motility in Active Droplets
复制标题
DOI：
10.1103/physrevx.11.011043
复制
发表时间：
2021-03-03
影响因子：
12.5
通讯作者：
Maass, Corinna C.
中科院分区：
文献类型：
--
作者：
Hokmabad, Babak Vajdi;Dey, Ranabir;Maass, Corinna C.
人工模型游泳者提供了一个平台来探索实现生物复杂性的物理原理，例如，多步态运动：许多生物微观游泳者采用的一种策略来探索和应对环境的变化。在这里，我们报告双峰运动在自泳液滴游泳者，驱动的特征界面流动模式为每个推进模式。我们展示了一个动态的过渡，从准弹道双峰混沌推进通过控制环境的粘度。为了阐明这一转变的物理机制，我们同时可视化的流体动力学和化学领域，并解释这些观测定量比较建立对流扩散模型。我们发现，随着粘度的增加，更高的流体动力学模式变得可激发和液滴之间的两个主导模式，由于与自生的化学梯度的相互作用经常切换。这种类型的自我互动促进自我回避的步行模仿在自然界中观察到的有效的空间探索策略的例子。
Artificial model swimmers offer a platform to explore the physical principles enabling biological complexity, for example, multigait motility: a strategy employed by many biomicroswimmers to explore and react to changes in their environment. Here, we report bimodal motility in autophoretic droplet swimmers, driven by characteristic interfacial flow patterns for each propulsive mode. We demonstrate a dynamical transition from quasiballistic to bimodal chaotic propulsion by controlling the viscosity of the environment. To elucidate the physical mechanism of this transition, we simultaneously visualize hydrodynamic and chemical fields and interpret these observations by quantitative comparison to established advection-diffusion models. We show that, with increasing viscosity, higher hydrodynamic modes become excitable and the droplet recurrently switches between two dominant modes due to interactions with the self-generated chemical gradients. This type of self-interaction promotes self-avoiding walks mimicking examples of efficient spatial exploration strategies observed in nature.