Continuous and precise modulation of vortex beams based on terahertz full-space coding metasurfaces

作者：Xin Yan, Fei Huai, Yonggang Zhang, Kaikai Lv, Lanju Liang, Zhenhua Li, Zhiguo Wang, Haiyun Yao, Xiaofei Hu, Yuanping Li, Meng Wang, Yang Liu, Shiwu Ma, Huihan Tian, Xuelin Wang, Jintao Wu · 发表于：Optics Express · 年份：2025 · DOI：10.1364/oe.554473 · 被引用次数：8 · 研究领域：Metamaterials and Metasurfaces Applications、Orbital Angular Momentum in Optics、Plasmonic and Surface Plasmon Research

Vortex beams carrying orbital angular momentum (OAM) exhibit excellent potential for applications in fields such as sixth-generation communication, quantum information processing, and imaging technologies. However, the realization of multi-mode and full-space continuous precision modulation of vortex beams still faces significant challenges. In this study, a terahertz full-space coding metasurface based on vanadium dioxide (VO 2 ) is proposed, combined with a more accurate generalized coding strategy, convolution, and generalized superposition methods to achieve continuous and precise modulation of vortex beams. First, the phase state of VO 2 is dynamically adjusted by temperature changes, enabling the coding metasurface to switch between transmission and reflection operating modes. Second, a precise generalized coding strategy is developed to support the generation of coding sequences for arbitrary Ni values by logically discretizing the size Ni of the super-subunit. Meanwhile, by convolving different coding sequences, continuous and precise modulation of different modes of vortex beams in the range of 0 to 360° is realized. Finally, the deflection vortex beams carrying different OAM are effectively superimposed using the generalized superposition method. This innovative coding strategy significantly improves the ability of continuous and precise modulation of the vortex beam wavefront, laying a solid foundation for future breakthroughs in intelligent communication and high-...