Activity-Suppressed Phase Separation
Activity-Suppressed Phase Separation
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活性抑制相分离
DOI：
10.1103/physrevlett.129.268002
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发表时间：
2022
影响因子：
8.6
通讯作者：
Marchetti, M. Cristina
中科院分区：
文献类型：
--
作者：
Caballero, Fernando;Marchetti, M. Cristina
我们使用一个连续介质模型来研究活动的效果相分离的混合物的可扩展的主动的电介质和被动的流体。我们强调的独特作用（一）以前考虑的界面主动应力和（ii）散装主动应力，耦合到液晶自由度。如前所述，界面活性应力可以阻止相分离。体积可伸展主动应力还可以通过流体的持续自搅拌来强烈地抑制相分离，从而相对于被动系统的尺寸显著减小温度集中平面中的共存区域的尺寸。相分离状态是一个动态的乳状液连续分裂和合并液滴，建议由最近的实验。使用缩放分析和模拟，我们确定各种制度的液滴大小对活动的依赖。这些结果可以为在实验中识别负责阻止相分离的机制提供标准。
We use a continuum model to examine the effect of activity on a phase-separating mixture of an extensile active nematic and a passive fluid. We highlight the distinct role of (i) previously considered interfacial active stresses and (ii) bulk active stresses that couple to liquid crystalline degrees of freedom. Interfacial active stresses can arrest phase separation, as previously demonstrated. Bulk extensile active stresses can additionally strongly suppress phase separation by sustained self-stirring of the fluid, substantially reducing the size of the coexistence region in the temperature-concentration plane relative to that of the passive system. The phase-separated state is a dynamical emulsion of continuously splitting and merging droplets, as suggested by recent experiments. Using scaling analysis and simulations, we identify various regimes for the dependence of droplet size on activity. These results can provide a criterion for identifying the mechanisms responsible for arresting phase separation in experiments.