[论文解读] Topological robustness of optical skyrmions through a real-world free-space link

Cade Peters, Vagharshak Hakobyan+4 more|arXiv (Cornell University)|Feb 4, 2026

Orbital Angular Momentum in Optics被引用 1

一句话总结

本文证明光学天球子在通过270 m现实世界自由空间通道传输时，尽管存在严重湍流和去极化，仍保持其拓扑包裹数，从而实现高保真信息传输。

ABSTRACT

Structured light offers a promising solution for the increasing data demands of modern optical networks, opening up new degrees of freedom that can be leveraged for greater channel capacity and more bits per photon. However, its implementation is hindered by real-world distortions, for example, atmospheric turbulence in free-space, with severe and rapidly evolving phase perturbations that alter the amplitude, phase and vectorial polarization structure of the beam. Here, we demonstrate that optical topologies in the form of skyrmions are highly resilient to the effects of real-world atmospheric turbulence. We create and transmit these particle-like topologies of light through a 270~m free-space optical link, revealing their robustness across a wide variety of conditions and turbulence strengths. While we observe severe distortion in the states' underlying degrees of freedom, we show that the topological numbers are preserved in all cases. We account for fast changes to the medium, where the channel produces statistically averaged outcomes, by probing the state's decoherence, showing that while the degree of polarisation consequently decays, the topology remains intact. Using topology, we show information can be transmitted through the channel with almost perfect fidelity (>98%) in most cases, only decreasing to 86% in the most severe conditions tested. Our work is the first to demonstrate the potential for optical topologies as reliable and robust information carriers in a real-world environment and points to the potential for other complex channels too, offering attractive features for classical and quantum communication alike.

研究动机与目标

• 通过利用拓扑不变量来开发结构化光以获得更高容量的光通信的动机。
• 展示光学天球子在自由空间链路中对现实世界大气湍流的鲁棒性。
• 量化湍流、去相干和去极化如何影响拓扑与信息保真度。
• 评估在经过湍流信道的情况下，基于拓扑的编码在经典与量子通信中的可行性。

提出的方法

• 使用带有受控的 l1、l2 的 Laguerre-Gaussian 组件生成光学天球子作为矢量光束以设定天球子数 N。
• 通过270 m outdoor free-space链路传输这些光束。
• 使用对偏振敏感的相机一次测量四个Stokes参数以重建偏振态和Stokes纹理。
• 通过映射的Stokes纹理计算天球子包裹数 N，公式为 N = (1/4π) ∫ S · (∂xS × ∂yS) dx dy（对于这些态简化为 N = n|l1−l2|）。
• 在一天中不同时间（早晨、正午、下午晚些时候）和不同的闪烁强度 σI^2 下评估鲁棒性，并通过时间平均实现去极化。
• 演示在有湍流的通道中实现高保真信息传输（基于拓扑）而无需通道探测或前/后补偿。

Figure 1: Skyrmionic topology through turbulence . Illustration showing how optical skyrmions are formed via a mapping from the transverse plane to the Poincaré sphere, characterised by the skyrmion number $N$ . When these states pass through a turbulent channel, the beam’s structure is heavily dist

实验结果

研究问题

• RQ1 当矢量光束穿过现实世界的湍流自由空间通道时，天球子包裹数是否保持不变？
• RQ2 大气湍流（包括去相干与去极化）如何影响天球子拓扑性与信息保真度？
• RQ3 在现实通道条件、不同时间段下，基于拓扑的编码是否能维持高保真？
• RQ4 光学天球子在自由空间链路中对鲁棒的经典与量子通信潜力有多大？

主要发现

• 天球子数在通道中从平静到高度湍流条件下保持鲁棒，Nexp 与编码的 N 非常接近（例如早晨数据中 Nexp = 0.81±0.01 对于 N=1，Nexp = 2.063±0.003 对于 N=2）。
• 拓扑映射在光束幅度、相位与偏振被湍流严重扭曲时仍然保持。
• 去极化/去相干导致DoP下降至约 0.39，但天球子数几乎保持不变（N ≈ 编码的 N）。
• 通过天球子拓扑编码的信息在大多数条件下实现几乎完美的保真度（>98%），在最严重的情况下也达到 86% 的下限。
• 通过拓扑重建的传输图像保持结构完整性：早晨保真度 98.70%，平均 240 ms 下 depolarization 的保真度 99.72%。
• 结果确立光学天球子作为在现实世界湍流通道中用于经典与量子通信的鲁棒信息载体。

Figure 2: Generation and detection through a free space link. a . Optical skyrmions were generated using complex amplitude holograms to generate two scaler modes. These modes were vectorially combined with a Mach-Zehnder interferometer and transmitted through a 270 m free space optical link. At the