液晶与显示, 2018, 33 (12): 1002, 网络出版: 2019-01-15  

同心柱筒中混合排列向列相液晶中的挠曲电效应

Flexoelectric effect of hybrid aligned nematic liquid crystals in concentric cylinders
作者单位
河北工业大学 理学院, 天津 300401
摘要
本文研究径向电场作用下同心柱筒中混合排列向列相液晶的指向矢分布, 重点研究挠曲电效应对指向矢分布的影响。向列相液晶处于同心圆柱构成的薄层间, 内表面径向锚定、外表面轴向锚定以及内表面轴向锚定、外表面径向锚定构成两种同心柱筒混合排列模型。基于向列相液晶Frank弹性理论, 通过差分迭代方法, 分别在强锚定及弱锚定边界条件下, 研究了两种模型中挠曲电效应对指向矢分布的影响。研究结果表明: 挠曲电效应在薄层内边界、外边界以及薄层内部对指向矢分布有着不同的影响; 同心柱筒中指向矢分布由柱对称性、边界锚定作用、介电耦合作用、挠曲电效应的综合作用所决定。
Abstract
The director distribution of the hybrid aligned nematic liquid crystal in concentric cylinders under a radial electric field is studied. The influence of the flexoelectric effect on director distribution is mainly studied. The nematic liquid crystals are in the thin layer of concentric cylinders, in which the radial anchoring of the inner surface and the axial anchoring of the external surface, or the axial anchoring of the inner surface and the radial anchoring of the external surface constitute two hybrid aligned nematic liquid crystals models. Based on the Frank elastic theory of nematic liquid crystal, the influence of the flexoelectric effect on the director distribution in the two models is studied under the strong anchoring and weak anchoring boundary conditions by the finite-difference iterative method. The study shows that the influence of the flexoelectric effect on the director distribution is different in the inner boundary, the outer boundary and the thin layer, and that the director distribution in the thin layer is determined by the comprehensive effect of cylindrical symmetry, boundary anchoring strength, dielectric effect and flexoelectric effect.
参考文献

[1] 杨傅子.近期液晶研究中的几个新方向——液晶非显示应用基础研究的进展[J].物理学进展, 2008, 28(2): 107-129.

    YANG F Z. New directions in recent liquid crystal studies——the progress in foundational research of non-display application of liquid crystals [J]. Progress in Physics, 2008, 28(2): 107-129. (in Chinese)

[2] DZYALOSHINSKI I E. Theory of disinclinations in liquid crystals [J]. Soviet Journal of Experimental and Theoretical Physics, 1970, 31: 773-780.

[3] CLADIS P E, KLMAN M. Non-singular disclinations of strength S = + 1 in nematics [J]. Journal de Physique, 1972, 33(5/6): 591-598.

[4] LANDAU L D, LIFSHITZ E M. Theory of Elasticity: Course of Theoretical Physics [M]. 3rd ed. New York: Pergamon Press, 1986: 1385.

[5] ALLENDER D W, CRAWFORD G P, DOANE J W. Determination of the liquid-crystal surface elastic constant K24 [J]. Physical Review Letters, 1991, 67(11): 1442-1445.

[6] CRAWFORD G P, ALLENDER D W, DOANE J W. Surface elastic and molecular-anchoring properties of nematic liquid crystals confined to cylindrical cavities [J]. Physical Review A, 1992, 45(12): 8693-8708.

[7] KRALJ S, UMER S. Saddle-splay elasticity of nematic structures confined to a cylindrical capillary [J]. Physical Review E, 1995, 51(1): 366-379.

[8] BURYLOV S V. Equilibrium configuration of a nematic liquid crystal confined to a cylindrical cavity [J]. Journal of Experimental and Theoretical Physics, 1997, 85(5): 873-886.

[9] 刘红红, 张艳君.混合排列柱状薄层中的向列相液晶指向矢分布的研究[J].液晶与显示, 2017, 32(1): 13-18.

    LIU H H, ZHANG Y J. Director distributions of nematic liquid crystals in hybrid arrangement cylindrical cells [J]. Chinese Journal of Liquid Crystals and Displays, 2017, 32(1): 13-18. (in Chinese)

[10] CORELLA-MADUEO A, REYES J A. Electrically controlled liquid crystal fiber [J]. Optics Communications, 2006, 264(1): 148-155.

[11] CORELLA-MADUEO A, CASTELLANOS-MORENO A, GUTIRREZ-LPEZ S, et al. Threshold field for a nematic liquid crystal confined between two coaxial cylinders [J]. Physical Review E, 2008, 78(2): 022701.

[12] DESOUZA R T, DIAS J C, MENDES R S, et al. Critical exponents for Fréedericskz transition in nematics between concentric cylinders [J]. Physica A: Statistical Mechanics and Its Applications, 2010, 389(5): 945-950.

[13] MEYER R B. Piezoelectric effects in liquid crystals [J]. Physical Review Letters, 1969, 22(18): 918-921.

[14] 郑桂丽, 张辉, 叶文江, 等.全漏光导波技术确定液晶材料的挠曲电系数[J].光子学报, 2014, 43(12): 51-55.

    ZHEND G L, ZHANG H, YE W J, et al. Determination of the flexoelectric coefficient in liquid crystal using fully-leaky optical guided wave technique [J]. Acta Photonica Sinica, 2014, 43(12): 51-55. (in Chinese)

[15] 张晶, 周璇, 陈思博, 等.向列相液晶畴壁中挠曲电效应和自发扭曲效应的理论研究[J].液晶与显示, 2018, 33(1): 1-13.

    ZHANG J, ZHOU X, CHEN S B, et al. Theoretical study of flexoelectric effect and spontaneous distortion in domain walls within nematic liquid crystal system [J]. Chinese Journal of Liquid Crystals & Displays, 2018, 33(1): 1-13. (in Chinese)

[16] KOTOV I V, KHAZIMULLIN M V, KREKHOV A P. Flexoelectric instability in nematic liquid crystal between coaxial cylinders [J]. Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals, 2001, 366(1): 885-892.

[17] FRANK F C. I. Liquid crystals. On the theory of liquid crystals [J]. Discussions of the Faraday Society, 1958, 25(25): 19-28.

[18] RAPINI A, PAPOULAR M. Distortion d’une lamelle nématique sous champ magnétique conditions d’ancrage aux parois [J]. Journal de Physique Colloques, 1969, 30(C4): 54-56.

[19] LIU H H, ZHANG Y J, YUE H R, et al. Influence of flexoelectric effect on director alignment of nematic liquid crystals in axial arrangement cylindrical cells [J]. Chinese Physics Letters, 2018, 35(2): 026103.

常雨珂, 张艳君, 叶文江. 同心柱筒中混合排列向列相液晶中的挠曲电效应[J]. 液晶与显示, 2018, 33(12): 1002. CHANG Yu-ke, ZHANG Yan-jun, YE Wen-jiang. Flexoelectric effect of hybrid aligned nematic liquid crystals in concentric cylinders[J]. Chinese Journal of Liquid Crystals and Displays, 2018, 33(12): 1002.

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