Grid pattern emerging from complex dynamics of defects
Grid pattern emerging from complex dynamics of defects
复制标题
从缺陷的复杂动态中出现的网格图案
DOI：
10.1103/physreve.101.062204
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发表时间：
2020
影响因子：
2.4
通讯作者：
Tomohiro Gunji and Yoshiki Hidaka
中科院分区：
文献类型：
--
作者：
Noriko Oikawa;Tomohiro Gunji and Yoshiki Hidaka
研究了向列液晶电对流中的一种细胞对流模式——网格模式的形成过程和生长动力学。随着外加电压的增加，栅格图案通过一种称为缺陷湍流的无序状态出现。平均缺陷密度随外加电压的增加而增加，然后在连续产生和湮灭过程中的缺陷被冻结为网格细胞形成域结构。采用网格域的面积分数作为阶参量。还测量了阶跃电压的面积分数随时间的增长。通过将Kolmogorov-Avrami模型应用于结果，表明网格域的生长动力学主要不是由区域生长控制的，而是由滚动通过暂时出现的初步网格结构局部过渡到细胞流控制的。
The formation process and growth dynamics of the grid pattern, a cellular convective pattern in the electroconvection of nematic liquid crystals, are investigated. The grid pattern appears via a disordered state called defect turbulence with the increasing of an applied voltage. The averaged defect density increases with the applied voltage and then the defects that have been in the continuous process of creation and annihilation are frozen as grid cells forming domain structures. The area fraction of the grid domains is adopted as the order parameter. The temporal growth of the area fraction for the step voltage was also measured. By applying the Kolmogorov-Avrami model to the results, it is suggested that the growth dynamics of the grid domain is not primarily governed by domain growth, but by the local transition of the rolls to the cellular flow via preliminary grid structures that transiently appear.