Single-mode fiber and few-mode fiber photonic lanterns performance evaluated for use in a scalable real-time photon counting ground receiver
Single-mode fiber and few-mode fiber photonic lanterns performance evaluated for use in a scalable real-time photon counting ground receiver
复制标题
单模光纤和少模光纤光子灯笼性能评估用于可扩展的实时光子计数地面接收器
DOI：
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发表时间：
2019
期刊：
影响因子：
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通讯作者：
R. Lafon
中科院分区：
文献类型：
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作者：
S. Tedder;Brian E. Vyhnalek;S. Leon;C. Betters;Bertram Floyd;Jeremy Staffa;R. Lafon
光子灯提供了一种将光从单个大芯光纤耦合到多个小芯光纤的有效方法。此功能对于空对地通信应用很有意义。在这些应用中，光学地面接收器需要从大气扭曲焦点到多个光纤耦合的单像素超导纳米线探测器的高效耦合。本文将探讨光子灯笼在实时地面接收器中的使用，该接收器可扩展并由商业部件构建。制造光子灯的小芯光纤（即单模或少模芯阵列）的数量决定了它们在较大的多模光纤芯端耦合的空间模式的数量。例如，由 n 个单模光纤制成的灯笼可以耦合 n 个空间模式。尽管从航天器发射的激光最初是高斯形状，但大气层通过扰乱相位并将能量散射到高阶空间模式来扭曲光束轮廓。因此，如果地面接收器的尺寸适合具有 n 个检测器的目标数据速率，则由单模光纤制成的相应灯笼将耦合 n 个空间模式。散射到高于 n 的空间模式的发射光束的大部分能量将被损失。本文表明，可以通过用少模光纤而不是单模光纤制作灯笼来减少这种损耗，增加可以耦合的空间模式的数量，从而提高单像素、单光子探测器的耦合效率。在一定范围的自由空间耦合数值孔径和模场直径上比较了这两种类型的光子灯的自由空间与光纤耦合效率。结果表明，少模光纤灯笼在较高湍流条件下对于较长焦距的望远镜具有较高的耦合效率。还介绍了对灯笼添加到系统中的抖动的分析，表明少模光纤光子灯笼比单模光纤灯笼添加了更多的抖动，但比多模光纤添加的抖动要少。
Photonic lanterns provide an efficient way of coupling light from a single large-core fiber to multiple small-core fibers. This capability is of interest for space to ground communication applications. In these applications, the optical ground receivers require high-efficiency coupling from an atmospherically distorted focus spot to multiple fiber coupled single pixel super-conducting nanowire detectors. This paper will explore the use of photonic lanterns in a real-time ground receiver that is scalable and constructed with commercial parts. The number of small-core fibers (i.e. an array of single or few-mode cores) that make a photonic lantern determines the number of spatial modes that they couple at the larger multimode fiber core end. For instance, lanterns made with n number of single-mode fibers can couple n number of spatial modes. Although the laser transmitted from a spacecraft originates as a Gaussian shape, the atmosphere distorts the beam profile by scrambling the phase and scattering energy into higher-order spatial modes. Therefore, if a ground receiver is sized for a target data rate with n number of detectors, the corresponding lantern made with single-mode fibers will couple n number of spatial modes. Most of the energy of the transmitted beam scattered into spatial modes higher than n will be lost. This paper shows this loss may be reduced by making lanterns with few-mode fibers instead of single-mode fibers, increasing the number of spatial modes that can be coupled and therefore increasing the coupling efficiency to single pixel, single photon detectors. The free space to fiber coupling efficiency of these two types of photonic lanterns are compared over a range of the free-space coupling numerical apertures and mode field diameters. Results indicate the few mode fiber lantern has higher coupling efficiency for telescopes with longer focal lengths under higher turbulent conditions. Also presented is analysis of the jitter added to the system by the lanterns, showing the few-mode fiber photonic lantern adds more jitter than the single-mode fiber lantern, but less than a multimode fiber.
影响因子：
27.1
作者：
Birks, T. A.;Gris-Sanchez, I.;Thomson, R. R.
通讯作者：
Thomson, R. R.