π相位板产生矢量光束的高数值孔径聚焦特性研究  

Study on High-Numerical-Aperture-Focused Characteristics of Vector Beam Produced by π Phase Plate

作　　者：陈国钧[1,2] 周巧巧[3] 纪宪明[2,3] 印建平[2] 

机构地区：[1]南通农业职业技术学院,江苏南通226007 [2]华东师范大学精密光谱科学与技术国家重点实验室,上海200062 [3]南通大学理学院,江苏南通226007

出　　处：《光学学报》2014年第12期292-299,共8页Acta Optica Sinica

基　　金：国家自然科学基金(11034002;11274114);科技部量子调控重大研究计划(2011CB921602);华东师范大学精密光谱科学与技术国家重点实验室开放基金

摘　　要：借助马赫曾德尔干涉仪光路,用简单的π相位板把线偏振光转换为径向和角向矢量空心光束,应用RichardsWolf经典矢量衍射模型,计算了高数值孔径透镜聚焦条件下光波电磁场的分布,结果表明:用10-3 W量级的激光功率照明,产生轴对称矢量空心光束的最大光强达到1011 W·m-2量级,最大光强梯度达到1017 W·m-3量级,暗斑半径仅有0.24λ,同时出现了很强的纵向电场和磁场分布;调节干涉仪光路的光程差可调节局域光子轨道角动量密度的分布,这种光束在原子光学中有很好的应用前景。Linear polarized light is converted to radial and angular vector hollow beams by using Mach-Zehnder interferometer light path with n phase plate. The distribution of the electromagnetic field focused with high numerical aperture is calculated by employing the Richards-Wolf classical vector diffraction model. The results show that the maximum intensity and intensity gradient of the axisymmetric vector hollow beam can respectively reach the magnitude of 10^11 ·m^-2 and 10^17 W·m^-3 under the illumination of laser with the power of 10 3 W magnitude, and the radius of the dark spot is only 0.24λ. Meanwhile, strong distributions of the longitudinal electric and magnetic fields are produced. The density distribution of the local photon orbital angular momentum can be adjusted by regulating the optical path difference of the interferometer. Therefore, this beam has good application prospect in atomic optics.

关 键 词：相干光学 矢量空心光束 原子光学 π相位板 坡印廷矢量 

分 类 号：O431.1[机械工程—光学工程]