• RESEARCH ARTICLE

  On-chip vectorial structured light field manipulation by inverse design    

  Zijia Wang, Kunhao Lei, Shenglong Yang, Mengxue Qi, Jieren Song, Yuting Ye, Hui Ma, Yiting Yun, Qiwei Zhan, Da Li, Shixun Dai, Baile Zhang, Xiaoyong Hu, Lan Li, Erping Li, Hongtao Lin

  2026, 19 (2): 11.https://doi.org/10.2738/foe.2026.0011

  

Structured light, with its multidimensional control over amplitude, phase, space and frequency, is a key enabler for advanced technologies such as high-capacity communications, quantum information, and super-resolution imaging. Here, we propose a unified inverse-design methodology for arbitrary on-chip vectorial structured-light. Inspired by quantum-state representations, we describe complex vector fields as finite-dimensional vectors in a Hilbert space and introduce a transmission-matrix formalism that links input waveguide modes to target topological edge states. By combining this mapping with adjoint-based topology optimization, we obtain the permittivity distribution within a compact design window that realizes the desired vector transformation while preserving topological transport. We experimentally demonstrate two representative domain-wall configurations on a valley photonic crystal (VPC) platform, termed Type-I and Type-II topological couplers, which efficiently couple the fundamental TE0 mode into valley pseudospin edge states. Simulations of the ideally designed device show insertion losses of 0.04 dB and 0.09 dB at 1550 nm with 3-dB bandwidths of 132 nm and 65 nm, respectively. Experimentally, the fabricated device, which was designed accounting for fabrication tolerances, maintains a broadband low-loss performance, with measured losses of < 0.6 dB at 1550 nm with 3-dB bandwidth over > 60 nm and < 0.8 dB at 1550 nm with 3-dB bandwidth over 87 nm. Mirror-symmetric designs further validate selective excitation of orthogonal pseudospin states. Our results establish this inverse-design methodology as a powerful tool for strictly controlling on-chip vectorial light, paving the way toward compact, broadband, and multifunctional photonic integrated circuits for optical computing, communications, and beyond.

一、研究背景

结构光的多维度可编程调控在光通信、量子信息和超分辨成像等领域具有重要价值，但传统自由空间实现依赖庞大精密装置，难以实用化。片上光子集成回路（PIC）配合谷光子晶体（VPC）赝自旋拓扑边缘态，为紧凑化结构光操控提供了理想平台，然而精确矢量场调控的统一设计范式仍属空白，逆向设计有望突破这一瓶颈。

二、主要内容

该研究以量子态启发矢量场表示结合传输矩阵映射与伴随法拓扑优化，建立了片上矢量结构光逆向设计的统一方法学。基于硫系玻璃（Ge₂₅Sb₁₀S₆₅）VPC平台，实验演示了两种拓扑耦合器：I型实测损耗<0.6 dB、3 dB带宽>60 nm，II型实测损耗<0.8 dB、带宽>87 nm（1550 nm），与仿真高度吻合。镜像对称设计进一步验证了正交赝自旋态的选择性激发，且器件对急转弯和缺陷表现出鲁棒的拓扑传输特性。

三、创新点

（1）提出量子态启发的矢量场表示与传输矩阵映射相结合的逆向设计方法学，将任意片上矢量光场调控问题转化为可求解的拓扑优化问题，统一了片上结构光产生与操控的设计框架。

（2）在硫系玻璃谷光子晶体平台上实验实现了超低损耗（<0.6 dB）、宽带（>60 nm）的片上拓扑耦合器，将TE₀基模高效转换为谷赝自旋拓扑边缘态，仿真设计与实验结果高度吻合。

（3）通过镜像对称设计实现正交赝自旋态的选择性激发，验证了谷自由度作为片上结构光多维度操控额外维度的可行性，为多功能光子集成回路提供了新途径。

四、总结与展望

该研究提出的逆向设计方法学为片上矢量结构光的精确调控建立了统一框架，在保持拓扑传输鲁棒性的同时实现了紧凑、宽带、低损耗的器件性能。这一方法可推广至各类拓扑光子平台和多维度光场调控场景。未来可进一步将逆向设计与多功能器件（如波分复用器、光计算单元）相结合，探索大规模片上结构光处理系统在光通信、光计算和量子信息等领域的实际应用。

（以上文字包含AI生成内容，仅供参考，请以原文为准。）

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