Yan Xu, Guo Lixin, Cheng Mingjian, Li Jiangting
Opt Express. 2018 May 14;26(10):12605-12619. doi: 10.1364/OE.26.012605.
Orbital angular momentum (OAM) mode crosstalk induced by atmospheric turbulence is a challenging phenomenon commonly occurring in OAM-based free-space optical (FSO) communication. Recent advances have facilitated new practicable methods using abruptly autofocusing light beams for weakening the turbulence effect on the FSO link. In this work, we show that a circular phase-locked Airy vortex beam array (AVBA) with sufficient elements has the inherent ability to form an abruptly autofocusing light beam carrying OAM, and its focusing properties can be controlled on demand by adjusting the topological charge values and locations of these vortices embedded in the array elements. The performance of a tailored Airy vortex beam array (TAVBA) through atmospheric turbulence is numerically studied. In a comparison with the ring Airy vortex beam (RAVB), the results indicate that TAVBA can be a superior light source for effectively reducing the intermodal crosstalk and vortex splitting, thus leading to improvement in the FSO system performance.
大气湍流引起的轨道角动量（OAM）模式串扰是基于OAM的自由空间光（FSO）通信中常见的具有挑战性的现象。最近的进展推动了使用突然自动聚焦光束来减弱湍流对FSO链路影响的新实用方法。在这项工作中，我们表明具有足够元件的圆形锁相艾里涡旋光束阵列（AVBA）具有形成携带OAM的突然自动聚焦光束的固有能力，并且可以通过调整嵌入阵列元件中的这些涡旋的拓扑电荷值和位置来按需控制其聚焦特性。通过数值研究了定制的艾里涡旋光束阵列（TAVBA）在大气湍流中的性能。与环形艾里涡旋光束（RAVB）相比，结果表明TAVBA可以成为有效减少模式间串扰和涡旋分裂的优质光源，从而提高FSO系统性能。
