向列液晶中的光控永久光栅  

Light controlled permanent gratings in nematic liquid crystals

作　　者：裴延波[1] 姚凤凤[1] 孙秀冬[1] 

机构地区：[1]哈尔滨工业大学物理系,黑龙江哈尔滨150001

出　　处：《红外与激光工程》2007年第2期261-264,共4页Infrared and Laser Engineering

基　　金：国家自然科学基金资助项目(90201003);黑龙江省杰出青年科学基金

摘　　要：液晶中的光折变光栅在数据存储、实时全息术、干涉测量、光放大、相位共轭、光学图像处理和光束操控等领域具有潜在的应用价值。通过二波耦合的方法在掺C60的向列液晶中记录了永久光栅,该光栅的衍射特性能够被外加直流电场或以任意角度入射的、与记录光强度相当的一束平面光波控制。为了进一步了解光栅建立的机制,研究了在恒定外加直流电场下的电流动态过程,从而证明该光栅源于表面电荷的光调制。Photorefractive gratings in liquid crystals have potential applications in holographic data storage, real-time holography, holographic interferometry, optical amplification, phase conjugation, optical image processing and beam steering. Light controlled permanent gratings are studied by two-wave coupling. The diffraction characteristics of the grating can be controlled by the application of an external electric field, or a plane wave with comparative intensity, no matter what is the incident direction of the light. The dynamics of the current in dark as well as under illumination is investigated in order to explore the mechanism of the grating formation. It illustrates that the grating originates from the modulation of the surface charges.

关 键 词：液晶 光折变材料 衍射光栅 

分 类 号：O753.2[理学—晶体学]