具有特殊关联结构的部分相干涡旋光束的传输特性研究

涡旋光束具有螺旋型相位分布，携带的轨道角动量可作为信号传输与信息编码的载体。光束传输特性的表征、调控以及与随机介质相互作用的机理研究受到研究者的极大关注，在光通信、超分辨成像以及光学微操控等领域具有重要应用价值。目前部分相干涡旋光束的关联结构主要集中于高斯-谢尔模型，本项目基于光场关联结构调控，理论研究具有特殊关联结构的部分相干涡旋光束的传输特性。主要包括：研究非均匀关联部分相干涡旋光束经光学系统以及湍流大气传输的传输特性，通过合理调制可控参量获得新型空间分布光场；研究拉盖尔-高斯关联部分相干涡旋光束经各向同性和各向异性湍流大气传输的光学统计特性，寻找增强光束抗湍流扰动能力的有效途径；研究部分相干涡旋光束经象散系统的轨道角动量特性，探索简易便捷的方法，实现对轨道角动量的有效调控。本项目将丰富相干光学与奇点光学的理论基础，为自由空间光通讯等实际应用提供新视角。

Vortex beams with spiral phase carry orbital angular momentum, which has been recognized as a carrier of signal transmission and information encoding. Researches around the characterization, regulation, as well as the mechanism of interaction with random media have received more and more attention due to its various applications in optical communications, super-resolution imaging, optical micro-manipulation and elsewhere. So far the correlation functions of partially coherent vortex beams mainly take the form of Gausssian-Schell model, based on the modulation of coherence of light field, this project will carry out theoretical study of the propagation properties of partially coherent vortex beams with special correlation functions. Firstly, the propagation behaviors of non-uniformly correlated vortex beams through a thin lens and turbulent atmosphere are to be explored, it's expected to obtain some novel space-variant optical fields by reasonably varying the controllable parameters. Then we will investigate the optical statistic properties of Laguerre-Gaussian correlated vortex beams propagating through isotropic and anisotropic atmospheric turbulence, respectively. And some methods to make beams more resistant to the degrading effects of turbulence are proposed. Finally, we will study the evolutions of orbital angular momentum of partially coherent vortex beams passing through an astigmatic system to find a simple and convenient way to realize the control of orbital angular momentum. This project would lead to enrichment of coherent optics and singular optics, meanwhile, it opens a new scope for practical applications of vortex beams like free-space communication.