部分相干Airy光束在湍流大气中传输时的偏振特性  

Polarization characteristics of coherent partially Airy beams propagating in atmospheric turbulence

作　　者：杨爱林[1] 林强[1,2] 

机构地区：[1]浙江大学物理系光学研究所,杭州310027 [2]浙江工业大学理学院,杭州310023

出　　处：《物理学报》2014年第20期181-187,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61475139);国家重点基础研究发展计划(批准号:2013CB329501);中央高校基本科研业务费(批准号:2012FZA3001)资助的课题~~

摘　　要：研究了部分相干Airy光束在湍流大气中传输时的偏振特性,偏振保持度作为衡量偏振传输效果的一个重要参数.结果表明:部分相干Airy光束在湍流大气中传输足够远时,其偏振度会变回到初始值;而在自由空间中传输,光束的偏振度会保持在某一个特定值;在湍流大气中,当光束传输距离不是很远时,光束对称轴上的偏振度分布为Airy函数,但是当传输足够远时,该偏振度分布逐渐趋向于类高斯状;光束的束腰半径越大,相干长度越长,越有利于光束传输后偏振的保持;存在一个指数截断因子,使得光束的偏振保持度很差.这些结论对于Airy光束在通信领域中的应用具有重要的意义.The degree of polarization of partially coherent Airy beams propagating through atmospheric turbulence is studied in this paper. Polarization fidelity of the beams is used to judge the propagation effect, It is shown that the degree of polarization of partially coherent Airy beams propagating through atmospheric turbulence tends to its initiM value after it has propagated over a sufficient distance, and in free space the degree of polarization retains a certain value. The polarization distribution alone the symmetry axis is an Airy function if the propagation distance is not so long and evolves into a Gaussian-like profile when propagating at sufficient long distance in atmospheric turbulence. The polarization fidelity of the beams with larger waist width wo and larger coherence length σ0 is better. There is an exponential truncation factor which badly degrades the polarization fidelity. The results obtained in this paper are very useful for communication of Airy beams.

关 键 词：湍流大气 偏振度 相干度 

分 类 号：O357.5[理学—流体力学]