光源参数及大气湍流对电磁光束传输偏振特性的影响  

Effect of source parameters on polarization characteristics of electromagnetic beam propagating in atmospheric turbulence

作　　者：李成强[1,2] 王挺峰[1] 张合勇[1] 谢京江[3] 刘立生[1,2] 郭劲[1] 

机构地区：[1]中国科学院长春光学精密机械与物理研究所激光与物质相互作用国家重点实验室,长春130033 [2]中国科学院大学,北京100049 [3]中国科学院长春光学精密机械与物理研究所中国科学院光学系统先进制造技术重点实验室,长春130033

出　　处：《物理学报》2014年第10期114-121,共8页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61205143)资助的课题~~

摘　　要：根据光束扩展理论,以部分相干的电磁高斯-谢尔光束为研究对象,分析了电磁光束传输时其偏振特性的变化机理.结果表明,光源参数和大气湍流对电磁光束分量扩展的影响是导致传输过程中电磁光束偏振特性变化的原因.在真空中传输时,电磁光束两分量的相干性存在差异,导致传输时电磁光束两分量扩展快慢不同,从而引起传输路径上光束谱偏振度的变化.在大气湍流中,电磁光束两分量扩展的快慢与光源参数和大气湍流强度均有关,当传输路径较短时,电磁光束偏振变化主要与光源参数有关,变化特性与在真空中传输时的情况类似,而传输距离较远时,电磁光束偏振变化受大气湍流的影响明显,变化特性与在真空中传输时的情形存在不同.According to the theory of beam spreading and taking electromagnetic Gaussian Shell-model beam as an object of research, the change in its spectral degree of polarization is studied by numerical analysis. Based on the numerical results, the mechanism that governs the change in polarization of an electromagnetic beam on propagation is discussed. The results show that the beam spreading of two components of an electromagnetic beam results in the change in polarization of beam directly, and the beam spreading is determined by source parameters and atmospheric turbulence. The difference between beam spreading of two components induced by coherence leads to the change in polarization in free space. The change in degree of polarization is influenced by source parameters and turbulence on propagation in atmosphere. The result is similar to that in free space over relatively short distance, which is mainly governed by source parameters. With the enhancement of turbulence over a sufficiently long distance, the change in polarization in atmosphere is different from that in free space.

关 键 词：偏振 相干 大气湍流 

分 类 号：O436.3[机械工程—光学工程] O357.5[理学—光学]