Instability of a Biaxial Nematic Liquid Crystal Formed by Homeotropic Anchoring on Surface Grooves  

作　　者：ZHANG Zhi-Dong XUAN Li 张志东;宣丽(Department of Applied Physics,Hebei University of Technology,Tianjin 300401;State Key Lab of Applied Optics,Changchun Institute of Optics,Fine Mechanics and Physics,Chinese Academy of Sciences,Changchun 130033)

机构地区：[1]Department of Applied Physics,Hebei University of Technology,Tianjin 300401 [2]State Key Lab of Applied Optics,Changchun Institute of Optics,Fine Mechanics and Physics,Chinese Academy of Sciences,Changchun 130033

出　　处：《Chinese Physics Letters》2011年第10期161-164,共4页中国物理快报（英文版）

基　　金：Supported by the National Natural Science Foundation of China under Grant Nos.60878047 and 60736042;the Hebei Provincial Natural Science Foundation under Grant No.A2010000004;the Key Subject Construction Project of Universities in Hebei Province.

摘　　要：A method used to treat the elastic distortion of a uniaxial nematic liquid crystal induced by homogeneous anchoring on the surface grooves is generalized to biaxial nematic liquid crystals under the homeotropic anchoring condition.Employing some approximations for the elastic constants,we obtain an additional term in the elastic energy per unit area which depends on the angle between the minor director at infinity and the direction of the grooves,with a period ofπ/2.This leads to instability on the surface grooves so that two states with crossed minor directors are energetically indistinguishable.Our theoretical study explains why the homeotropic alignment method developed for uniaxial liquid crystals loses efficacy for biaxial nematics.

关 键 词：INFINITY alignment CONSTANTS 

分 类 号：O48[理学—固体物理]