SiO_2/TiO_2多层膜结构一维光子晶体光子禁带研究  

Photonic band gap in one-dimensional SiO_2/TiO_2 multilayer photonic crystal

作　　者：乌日娜[1] 闫彬[1] 王彦华[1] 徐送宁[1] 闫秀生 岱钦[1] 

机构地区：[1]沈阳理工大学理学院,辽宁沈阳110168 [2]光电系统信息控制国家重点实验室,河北三河065201

出　　处：《红外与激光工程》2011年第5期872-875,共4页Infrared and Laser Engineering

基　　金：国家自然基金(60578035);辽宁省自然科学基金(20102191);辽宁省教育厅科研项目(L2010465);沈阳科学技术计划项目(F10214100)

摘　　要：制作了SiO2/TiO2多层膜结构一维光子晶体,研究了其光子禁带特性。通过测量红外透射谱,分析了入射线偏振方向、入射角度以及引入缺陷层对光子禁带的影响。随着入射角度的增大,在TE模式和TM模式线偏振光下,光子禁带边沿产生蓝移现象。引入TEB30A型向列相液晶缺陷后,光子禁带中在波长约为1810nm(TE模式)和1821nm(TM模式)处出现了透射峰。利用传输矩阵理论,模拟计算了光子晶体透射谱,并对实验结果进行了深入分析。无缺陷时,随着入射角增大,薄膜的光学厚度减小,光子禁带边沿蓝移。引入液晶缺陷后,光子禁带中产生特定的缺陷态,和缺陷态频率相吻合的光子被局域在缺陷位置,禁带中出现透射峰。由于两种模式线偏振光下的液晶层光学厚度不同,透射峰位置也不同。One-dimensional（1D） multilayer photonic crystal（PC） with SiO2/TiO2 was designed and fabricated.The characteristics of photonic band gap（PBG） were investigated.The influences of the linearly polarized light,the incident angle and the introduced defect layers on the PBG were analyzed by measuring the infrared transmission spectra.The edge of PBG shifted to shorter wavelength when the incident angles of linearly polarized light of TE mode and TM mode increased.Transmission peaks appeared in photonic band gap and their center wavelengths were approximately 1 810 nm（TE） and 1 821 nm（TM） if defect layer of nematic liquid crystal TEB30A was introduced.The transmission spectrum of PC was simulated with the transfer matrix theory.The experimental results show that when there is no defect layer,the increasing of the incident angle brings a decreasing of optical thickness of the film,which results in a blue shift of the PBG edge.A specific defect state is produced in the PBG when introducing the liquid crystal defect layers.The photons which have the same frequency with the defect states are localized in the defect position and lead to the transmission peaks eventually.The transmission peaks positions of the TE mode and TM mode are different because the optical thickness of the liquid crystal layer is different at two polarized light modes.

关 键 词：光子晶体 透射谱 光子禁带 液晶缺陷层 

分 类 号：O753.2[理学—晶体学]