近日，北京理工大学付时尧团队研究了面向高维光子学的多自由度紧凑剪裁中的混合策略。该研究于2025年4月21日发表在《光：科学与应用》杂志上。

定制多自由度（DoF）以实现高维激光场对于推进光学技术至关重要。虽然最近的进展已经证明了操纵有限数量的自由度的能力，但大多数现有的方法都依赖于笨重的光学元件或复杂的系统，这些系统采用耗时的迭代方法，最关键的是，通过紧凑的单个元件同时按需定制多个自由度，这仍然没有得到充分的探索。

在这项研究中，课题组提出了一种智能混合策略，可以同时和可定制地操纵六个自由度：波矢量、初始相位、空间模式、振幅、轨道角动量（OAM）和自旋角动量（SAM）。该方法在纯相位特性方面取得了进展，这有助于在紧凑的元曲面上实验演示定制策略。制造的样品被定制为在六个自由度上实现任意操纵，构建了一个288维的空间。值得注意的是，由于OAM本征态构成了一个无限维的Hilbert空间，因此该建议可以进一步扩展到更高的维。

原理验证实验证实了操纵能力和维度的有效性。研究组设想，这种强大的定制能力为跨经典和量子场景的多功能光子器件提供了巨大的潜力，这种紧凑性扩展了集成片上要求的尺寸能力。

附：英文原文

Title: Hybrid strategy in compact tailoring of multiple degrees-of-freedom toward high-dimensional photonics

Author: Zhou, Shiyun, Li, Lang, Gao, Liliang, Zhou, Zhiyuan, Yang, Jinyu, Zhang, Shurui, Wang, Tonglu, Gao, Chunqing, Fu, Shiyao

Issue&Volume: 2025-04-21

Abstract: Tailoring multiple degrees-of-freedom (DoFs) to achieve high-dimensional laser field is crucial for advancing optical technologies. While recent advancements have demonstrated the ability to manipulate a limited number of DoFs, most existing methods rely on bulky optical components or intricate systems that employ time-consuming iterative methods and, most critically, the on-demand tailoring of multiple DoFs simultaneously through a compact, single element—remains underexplored. In this study, we propose an intelligent hybrid strategy that enables the simultaneous and customizable manipulation of six DoFs: wave vector, initial phase, spatial mode, amplitude, orbital angular momentum (OAM) and spin angular momentum (SAM). Our approach advances in phase-only property, which facilitates tailoring strategy experimentally demonstrated on a compact metasurface. A fabricated sample is tailored to realize arbitrary manipulation across six DoFs, constructing a 288-dimensional space. Notably, since the OAM eigenstates constitute an infinite dimensional Hilbert space, this proposal can be further extended to even higher dimensions. Proof-of-principle experiments confirm the effectiveness in manipulation capability and dimensionality. We envision that this powerful tailoring ability offers immense potential for multifunctional photonic devices across both classical and quantum scenarios and such compactness extending the dimensional capabilities for integration on-chip requirements.

DOI: 10.1038/s41377-025-01857-3

Source: https://www.nature.com/articles/s41377-025-01857-3