Relaxation of abnormal rolls in planarly aligned electroconvection
Relaxation of abnormal rolls in planarly aligned electroconvection
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DOI：
10.1103/physreve.59.1814
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发表时间：
1999-02
影响因子：
2.4
通讯作者：
S. Rudroff;V. Frette;I. Rehberg
中科院分区：
文献类型：
--
作者：
S. Rudroff;V. Frette;I. Rehberg
本文报道了平面取向液晶中电对流的实验结果。特别强调的是调查异常辊，其特点是在导演领域的扭曲的光学技术。用椭圆偏振法测量了扭转的序参量。我们还进行了数值研究的光学设置使用传输矩阵法。扭曲的弛豫时间已被测量，并与理论预测进行比较。特别地，发现异常辊中的扭曲迫使玻璃表面处的指向矢场偏离其优选方向-弱锚定！液晶锚定中的这种扭曲松弛比理论预测的由弹性力驱动的松弛过程慢一个数量级。@S1063-651X~99！09701-9#
Experimental results on electroconvection in a planarly aligned nematic liquid crystal are reported. Special emphasis is given to an optical technique for investigating abnormal rolls, which are characterized by a twist in the director field. The order parameter of the twist is measured by ellipsometry. We have also carried out a numerical investigation of the optical setup using a transfer-matrix method. The relaxation time of the twist has been measured and compared to theoretical predictions. In particular, it is found that the twist in the abnormal rolls forces the director field at the glass surface to turn away from its preferred direction ~weak anchoring !. This distortion in the anchoring of the liquid crystal relaxes one order of magnitude slower than theory predicts for relaxation processes driven by elastic forces in bulk. @S1063-651X~99!09701-9#