Observing Correlated Production of Defects-Antidefects in Liquid Crystals
نویسندگان
چکیده
We present observation of strength one defects and antidefects formed in isotropic-nematic phase transition in nematic liquid crystals using a crosspolarizer setup. We measure the width σ of the distribution of net winding number in two dimensional regions, each containing an average of 10 defects and antidefects. We find σ = 1.19± 0.04, in good agreement with the value 1.02 or 1.26 (for triangular or square domains) predicted by the Kibble mechanism for defect production. We also describe a novel technique to determine the director distribution in such observations. PACS numbers: 61.30.Jf, 98.80.Cq, 64.70.Md Typeset using REVTEX
منابع مشابه
Observing Correlated Production of Defects and Antidefects in Liquid Crystals
We present observations of strength one defects and antidefects formed in isotropic-nematic phase transition in a thin layer of nematic liquid crystals, using a cross-polarizer setup. We measure the widths of the distributions of net winding number in small regions, and determine the exponent characterizing the correlation between defects and antidefects to be 0.26±0.11, in very good agreement ...
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تاریخ انتشار 1999