大气湍流中两条相关刃型位错的相互作用  

Interaction of Two Coherent Edge Dislocations inAtmospheric Turbulence

作　　者：陈海涛[1] 杨华军 高曾辉[3] 刘学琼 Chen Haitao;Yang Huajun;Gao Zenghui;Liu Xueqiong(College of Physics and Engineering,Chengdu Normal University,Chengdu 611130,Sichuan,China;School of Physics,University of Electronic Science and Technology of China,Chengdu 610054,Sichuan,China;Key Laboratory of Computational Physics of Sichuan Province,Yibin University,Yibin 644000,Sichuan,China;Hejiang Middle School,Luzhou Municipal Education and Sports Bureau,Luzhou 646200,Sichuan,China)

机构地区：[1]成都师范学院物理与工程技术学院,四川成都611130 [2]电子科技大学物理学院,四川成都610054 [3]宜宾学院计算物理四川省高等学校重点实验室,四川宜宾644000 [4]泸州市教育和体育局合江中学,四川泸州646200

出　　处：《光学学报》2024年第18期191-201,共11页Acta Optica Sinica

基　　金：国家自然科学基金(11574042,61271167,61275203,61775188);四川省教育厅自然科学基金(18ZA0081)。

摘　　要：为了探究部分相干光束携带的两条相关刃型位错在大气湍流中的相互作用,提出了相关刃型位错的概念。基于扩展的惠更斯-菲涅耳原理,推导出了携带两条相关刃型位错的高斯-谢尔模光束在大气湍流中的交叉谱密度表达式,并讨论相关刃型位错在自由空间和大气湍流情形下的相互作用特点。研究表明:该光束携带的相关刃型位错因不稳定在传输中消失,但随着光束传输,有相关涡旋或刃型位错出现。由于光束传输中伴随相关涡旋的产生和消失,光场中相关光涡旋的数目会发生变化。两条相关刃型位错在自由空间和大气湍流中的相互作用规律并不相同。该研究结果对深入理解相关奇点光束在大气湍流中的传输特性并寻找其潜在应用有一定的参考价值。Objective Singular optics has been associated for decades with the study of phase singularities in fully coherent beams.There are two main types of phase singularities:optical vortices and edge dislocations.Recent research has shown that the correlation functions of partially coherent beams can also exhibit types of phase singularities.This has led to the introduction of a new type of singularity,namely the correlation vortex,which is similar to the optical vortex and is defined as a phase singularity of the two-point cross-spectral density(CSD)function of the fields.While much research has focused on fully coherent beams,partially coherent beams have practical advantages due to their greater resistance to degradation when propagating through random media.In addition to correlation vortices,we propose the existence of another type of correlation singularity:the coherent edge-dislocation.Therefore,we introduce the concept of the coherent edge dislocation carried by the Gaussian Schell-model(GSM)beams,since GSM is a classic example of a partially coherent beam.We then study the interaction of two coherent edge dislocations carried by GSM beams as they propagate through free space and atmospheric turbulence,both theoretically and numerically.Methods By drawing an analogy with edge dislocations in coherent beams,we show that coherent edge dislocation exists in partially coherent beams.Based on the extended Huygens-Fresnel principle,we derive the analytical expression for the CSD of GSM beams carrying two edge dislocations propagating through atmospheric turbulence.This expression is used to study their interaction in both free space and atmospheric turbulence.The positions of the correlation singularities of partially coherent beams in the z-plane can be determined from the real and imaginary components,as well as from the phase distribution of the spectral degree of coherence of the GSM beams.Results and Discussions The CSD of partially coherent beams has a well-defined phase with respect to two points,and the phase

关 键 词：奇点光学 部分相干光 相关奇点 大气湍流 

分 类 号：O436[机械工程—光学工程]