随机电磁脉冲光束的产生及其在谐振腔内传输特性的研究

The coherence and the polarization of the optical field are correlated. The random electromagnetic pulsed beam(REMPB) is a model which concerns the temporal coherence, spatial coherence and polarization together. The model can be applied to the studies of molecular imaging, atmospheric optical communication, pulse compression and so on. The proposal will be carried out in theories and experiments as follows: (1) the evolution characteristics of the REMPB propagate in optical resonator will be studied, the experimental system of generating the REMPB will be constructed, and therefore the related theories will be verified through the experiments. (2) A set of experimental system will be designed and constructed, by which the spatio-temporal coupling REMPB can be generated and measured. The modulation of the REMPB's propagation properties caused by the grating, aperture, prism and others will be studied. The evolution of the REMPB's spatio-temporal coherence, polarization and pulse width will be analyzed. (3) The propagation properties of the REMPB in optical resonator will be studied. The characteristics of the pulsed beam will be modulated by placing the grating, grating pair, aperture and other optical elements in optical resonator. This proposal aims to develop the propagation theory of the random electromagnetic beam and pulsed beam, and to construct the design theory of the relevant resonator. It will also lay a foundation for the direct output of the REMPB through modulation in resonator.

光场的相干性和偏振性是相互关联的，随机电磁脉冲光束是一种同时考虑光场时间相干性、空间相干性和偏振特性光束模型，该模型可应用于分子影像学、大气光通信、脉冲压缩等领域的相关研究。本项目将进行如下的理论和实验研究：(1)研究随机电磁光束在光学谐振腔内传输的演化特性，建立产生随机电磁光束的实验系统，并从实验上验证相关结论；(2)设计并建立一套产生和测量时空耦合的随机电磁脉冲光束的实验系统，研究光栅、光阑和棱镜等光学元件对脉冲光束传输特性的调制作用，分析脉冲光束的时空相干性、偏振特性和脉冲宽度等特性的演化规律；(3)研究随机电磁脉冲光束在光学谐振腔内的传输特性，通过在谐振腔内放置光栅、光栅对、光阑等元器件，调控脉冲光束的输出特性。本项目将丰富随机电磁光束和脉冲光束的传输理论，构建相应的谐振腔设计理论，为通过谐振腔内调制的方式直接输出随机电磁脉冲光束奠定基础。

随机电磁脉冲光束是一种同时考虑光场时间相干性、空间相干性和偏振特性光束，这类光束在粒子操控、光信息处理、大气光通信等领域有着广泛应用前景和研究价值。本项目从脉冲光束的这些时空域特相关特性出发，基于构建空间多高斯谢尔模光束模型的方法，在时间域提出了获得相干性满足非负限定条件的新型部分相干脉冲光束光源的模型；通过调制脉冲光源关联结构（相关函数）的方法，获得平顶的光脉冲，调制光源相关函数内核前沿、后沿的方法，获得脉冲宽度、脉冲间隔可调的光脉冲序；研究了随机光学边框型光束在湍流大气中的传输特性，通过构建初始光束的相关函数关联结构，在大气中传输一定的特征距离后可以形成光强分布各异的单一边框结构光束或是网状边框结构光束，并且在大气中传输到远场时，光强分布又回归高斯分布；基于湍流大气的各向异性特性，研究了各向异性湍流大气中随机电磁高斯谢尔模光束传输特性的演化，研究结果表明各向异性参数越大的越可以有效减少大气的湍流效应对光束传输的影响。. 本项目的研究内容丰富了部分相干的随机电磁光束光源理论，拓展了其在时空域的研究，开拓了随机电磁光束在各向异性湍流大气中传输的研究。研究结果在光学信息变换、信息编码领域具有潜在的应用价值，在大气激光通信和成像中也有很好的应用前景。