Fringing field-induced monodomain of a polymer-stabilized blue phase liquid crystal

• Published in: Applied physics letters 2015-12, Vol.107 (24)
• Main Authors: Li, Wei-Huan, Hu, De-Chun, Li, Yan, Chen, Chao Ping, Lee, Yung-Jui, Lien, Alan, Lu, Jian-Gang, Su, Yikai
• Format: Article
• Language: English
• Subjects: Anchoring; Applied physics; Birefringence; Electric fields; Liquid crystals; Photopolymerization; Polymers; Polystyrene resins; Potential energy; Response time; Thermal stability
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.4938072

The influence of fringe electric field applied during photopolymerization on the electro-optic properties of polymer-stabilized blue phase liquid crystals (PS-BPLCs) was investigated. It has been found that the thermal stability would not degrade if the electric field was less than a critical value. The contrast ratio of PS-BPLC can be improved significantly because the uniformity of blue phase liquid crystal domain was enhanced by the electric fields, which were applied during photopolymerization. Meanwhile, with the electric filed, the potential energy of the BPLC molecules may lower the anchoring energy of the polymer network resulting in the improvement of electro-optic response properties. With optimized electric field during polymerization, the contrast ratio and the Kerr constant of PS-BPLC can be improved by 4.1 times and 15%, respectively, and the hysteresis can be decreased by 10%, while the response time and residual birefringence have no degradation.