Threshold and saturation properties of the field-induced twist cell with two parameters weak anchoring boundaries  

作　　者：关荣华 孙玉宝 

机构地区：[1]Department of Applied physics, North China Electric Power University, Baoding 071003, China [2]Department of Applied Physics, Hebei University of Technology, Tianjin 300130, China

出　　处：《Chinese Physics B》2006年第5期1041-1050,共10页中国物理B（英文版）

基　　金：Project supported by the Theoretical Physics Special Foundation of the National Natural Science of China （Grant No 10447107）, the Natural Science Foundation of Hebei Province, China （Grant No A2006000675）, the Doctoral Foundation of Hebei Province, China （Grant No 05547001D-3）, the Key Project Foundation of North China Electric Power University, China （Grant No 200513002） and the Key Construction Project of Hebei Provincial University, China.

摘　　要：On the basis of two-parameter formula of weak surface coupling anchoring energy of nematic liquid crystals proposed by Zhao et al recently, the general torque equilibrium equation and boundary conditions of the director have been obtained and the threshold field as well as the saturation field of the field-induced twist cell have been analysed for three kinds of configurations, i.e. homogeneous, splay and Pi ceils formed by different rubbing conditions and pretilt angles. The results indicated that the polar anchoring has no effect on the threshold field. It is determined only by the twist anchoring and pretilt angle. But, the polar anchoring and twist anchoring are coupling with each other and have a great influence on the saturation field. The formulae for calculating the threshold field and saturation field are given. These results will be very useful in understanding surface physics and the design of liquid crystal cells.On the basis of two-parameter formula of weak surface coupling anchoring energy of nematic liquid crystals proposed by Zhao et al recently, the general torque equilibrium equation and boundary conditions of the director have been obtained and the threshold field as well as the saturation field of the field-induced twist cell have been analysed for three kinds of configurations, i.e. homogeneous, splay and Pi ceils formed by different rubbing conditions and pretilt angles. The results indicated that the polar anchoring has no effect on the threshold field. It is determined only by the twist anchoring and pretilt angle. But, the polar anchoring and twist anchoring are coupling with each other and have a great influence on the saturation field. The formulae for calculating the threshold field and saturation field are given. These results will be very useful in understanding surface physics and the design of liquid crystal cells.

关 键 词：threshold field saturation field two-parameter formula nonzero pretilt angle 

分 类 号：O415[理学—理论物理]