Instability of a Biaxial Nematic Liquid Crystal Formed by Homeotropic Anchoring on Surface Grooves
ZHANG Zhi-Dong1** , XUAN Li2
1Department of Applied Physics, Hebei University of Technology, Tianjin 300401 2State Key Lab of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033
Instability of a Biaxial Nematic Liquid Crystal Formed by Homeotropic Anchoring on Surface Grooves
ZHANG Zhi-Dong1** , XUAN Li2
1Department of Applied Physics, Hebei University of Technology, Tianjin 300401 2State Key Lab of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033
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 of π/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.
Abstract：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 of π/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.
ZHANG Zhi-Dong**;XUAN Li
. Instability of a Biaxial Nematic Liquid Crystal Formed by Homeotropic Anchoring on Surface Grooves[J]. 中国物理快报, 2011, 28(10): 106101-106101.
ZHANG Zhi-Dong**, XUAN Li
. Instability of a Biaxial Nematic Liquid Crystal Formed by Homeotropic Anchoring on Surface Grooves. Chin. Phys. Lett., 2011, 28(10): 106101-106101.
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2011, Vol. 28 
