活动液晶的同位相中的旋转相分离和缺陷格子
Fernando Caballero1, Zhihong You2, M Cristina Marchetti1
1Department of Physics, University of California Santa Barbara, Santa Barbara, CA 93106, USA. fcaballero@brandeis.edu.
Soft matter
|October 5, 2023
概括
在活性液晶中调整基质摩擦会产生新的结构,比如带有缺陷的. 这项研究揭示了摩擦是控制这些复杂材料中活跃流动和新兴模式的关键参数.
科学领域:
- 软物质物理学 软物质物理学
- 活体物质系统是什么
- 液晶的动力学 液晶的动力学
背景情况:
- 被动液晶系统在研究的模式下通常是同位素的.
- 活跃液晶中的扩展活动可以破坏静止状态的稳定,导致混乱的动态.
研究的目的:
- 为了研究基板摩擦对活性液晶膜动态的影响.
- 在不同的摩擦条件下识别和描述新出现的结构和流动模式.
主要方法:
- 在基板上的活性液晶薄膜的数值模拟.
- 线性稳定性分析以了解不稳定机制.
- 参数空间的探索,包括活动和基板摩擦.
主要成果:
- 调节基板摩擦导致各种各样的新兴结构在中间活动.
- 观察到的现象包括具有拓缺陷的流动的格子.
- 一个新的状态特征是状 - 缺陷对形成六角格子,周围有反旋转的流.
结论:
- 基板摩擦是一种可以实验调节的参数,用于控制活跃的流量和设计新出现的模式.
- 新出现的结构是旋转的相位分离的结果,摩擦作用打破了保存定律.
- 图案的长度尺度是由流量选长度决定的,受粘度和摩擦的影响.
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