偏振度对部分相干拉盖尔-高斯谢尔模型光束漂移的影响  

Influence of the Degree of Polarization on Beam Wander of Partially Coherent Laguerre-Gaussian-Schell Model Beam

作　　者：代雯[1] 吴国华[1] 

机构地区：[1]北京邮电大学电子工程学院,北京100876

出　　处：《中国激光》2015年第B09期222-227,共6页Chinese Journal of Lasers

基　　金：国家自然科学基金（61471051）

摘　　要：研究了当部分相干拉盖尔-高斯谢尔模型（LGSM）光束在大气湍流中传输时，偏振度对光束漂移的影响。依据交叉谱密度函数和广义惠更斯积分原理，理论上推导出了部分相干LGSM光束的长期束宽和光束漂移表达式。通过仿真不同偏振度的LGSM光束随着传输距离、湍流强度和相干长度变化的光束漂移，研究偏振度对光束漂移的影响。仿真结果表明，部分相干LGSM光束的偏振度越大，相干长度越小，产生的光束漂移越小。这对自由空间光通信（FSO）中，有效降低光束漂移有重要意义。Influence of the degree of polarization on beam wander of partially coherent Laguerre-Gaussian-Schell model （LGSM） beams propagating in a turbulence atmosphere is investigated. Based on the cross-spectral density function and the extended Huygens-Fresnel integral principle, the expression for beam width and beam wander of partially coherent LGSM beams in theory is developed. In different transmission distances, turbulence strength and coherence length, influence of the degree of polarization on beam wander of partially coherent LGSM beams is illustrated numerically. The numerical results show that beam wander of a LGSM beam with larger degree of polarization and less coherent length is smaller. Therefore, in free-space optical （FSO） communication, we can choose beams with larger degree of polarization and smaller coherent length to reduce the beam wander.

关 键 词：相干光学 偏振度 光束漂移 相干长度 大气湍流 

分 类 号：TN929.12[电子电信—通信与信息系统]