光折变液晶系统的表面电荷调制模型  

Surface-charge modulation model in photorefractive liquid crystal system

作　　者：任常愚[1] 魏英智[1] 裴延波[2] 

机构地区：[1]黑龙江科技学院理学院,哈尔滨150027 [2]哈尔滨工业大学物理系,哈尔滨150001

出　　处：《黑龙江科技学院学报》2011年第3期229-232,共4页Journal of Heilongjiang Institute of Science and Technology

基　　金：黑龙江省自然科学基金项目(A200915);黑龙江省教育厅科学技术研究项目(12511493)

摘　　要：为了研究载流子的注入对液晶盒中电压的影响,构建了光折变液晶系统中表面电荷调制的载流子注入模型。在外加直流电场的作用下,液晶中的载流子向表面聚集,形成界面双电层。该双电层屏蔽了大部分的外加电场,使外加电压基本上都降落在界面双电层上。非均匀光照射时,在光亮区,来自于ITO电极的电荷将越过界面,产生载流子复合。而处于暗区的表面电荷密度基本保持不变,界面电荷层继续屏蔽外加电场,在液晶体内形成了与光强空间分布相对应的空间电荷场。基于以上模型,给出了界面附近的载流子和电场的动态演化过程,理论分析与已有的实验结果非常吻合。Aimed at investigating the effect of carrier injection on the voltage in a nematic liquid crystal cell,this paper introduces a surface-charge modulation model involving charge carriers injection of a photorefractive liquid crystal system.The charge carriers,subjected to DC voltage application,gather on the interfaces,with a resultant the electrical double layer,which may shield the most of the applied electric field,allowing the applied voltage basically to land on the electrical double layer at the interface.In the case of the non-uniform illumination,in the bright zone,the charge carriers from the ITO electrode hops through the interface,with the consequent recombination with opposite charged counter ions.The charge carrier＇s density in the dark areas at the s interface remains unchanged and interface charge layer continues to shield the electric field,resulting in space-charge field corresponding to the spatial light intensity distribution in the NLC.The model,which describes the charge carrier＇s density and the electric field evolution near the interface features a theoretical analysis consistent with the existing and experimental results.

关 键 词：液晶系统 光折变效应 表面电荷调制 双电荷层 

分 类 号：O753.2[理学—晶体学]