Defect dynamics in active smectics induced by confining geometry and topology
Defect dynamics in active smectics induced by confining geometry and topology
复制标题
DOI：
10.1038/s42005-022-01064-1
复制
发表时间：
2022-04
影响因子：
5.5
通讯作者：
Zhi-Feng Huang;H. Löwen;A. Voigt
中科院分区：
文献类型：
--
作者：
Zhi-Feng Huang;H. Löwen;A. Voigt
不平衡系统中的持续动力学，特别是那些以湮灭和拓扑缺陷产生为特征的系统，已知涉及复杂的时空过程，并且被认为难以控制。这里通过活性粒子的自推进和具有不同拓扑的各种约束几何形状（从圆形、花形外摆线到内摆线空腔、通道和环），探索暴露于强约束下的活性近晶层中缺陷的复杂动力学。我们在由限制形状和拓扑引起的复杂时空缺陷模式的演化过程中确定了丰富的动力学行为，特别是中间活动的永久创造-湮灭动态状态，拓扑缺陷的大波动以及通过边界尖点控制的机制从缺陷数密度的振荡到阻尼时间相关性的可控转变。我们的结果是通过使用活性相场晶体方法获得的。还讨论了可能的实验实现。
The persistent dynamics in systems out of equilibrium, particularly those characterized by annihilation and creation of topological defects, is known to involve complicated spatiotemporal processes and is deemed difficult to control. Here the complex dynamics of defects in active smectic layers exposed to strong confinements is explored, through self-propulsion of active particles and a variety of confining geometries with different topology, ranging from circular, flower-shaped epicycloid, to hypocycloid cavities, channels, and rings. We identify a wealth of dynamical behaviors during the evolution of complex spatiotemporal defect patterns as induced by the confining shape and topology, particularly a perpetual creation-annihilation dynamical state at intermediate activity with large fluctuations of topological defects and a controllable transition from oscillatory to damped time correlation of defect number density via mechanisms governed by boundary cusps. Our results are obtained by using an active phase field crystal approach. Possible experimental realizations are also discussed.