Microsystems & Nanoengineering (Oct 2024)

Tight focusing of fractional-order topological charge vector beams by cascading metamaterials and metalens

  • Lan Ke,
  • Yunyun Yang,
  • Mingmin Zhu,
  • Haomiao Zhou,
  • Yi Chen,
  • Ying Tian,
  • Chenxia Li,
  • Bo Fang,
  • Zhi Hong,
  • Xufeng Jing

DOI
https://doi.org/10.1038/s41378-024-00781-7
Journal volume & issue
Vol. 10, no. 1
pp. 1 – 17

Abstract

Read online

Abstract Vector beams have attracted widespread attention because of their unique optical properties; in particular, their combination with tight focusing can produce many interesting phenomena. The rise of 3D printing technology provides more possibilities for exploration. In this work, a cascading method involving a metamaterial and a metalens is used to generate a tightly focused field of vector beams in the terahertz band, which is prepared via 3D printing. As a proof-of-concept demonstration, a series of metamaterial modules capable of generating states of different orbital angular momentum are proposed by cascading with a metalens. The experimental results are in good agreement with the simulation results, fully verifying the feasibility of the scheme. The proposed design and fabrication strategy provides a new idea for the tight focusing of terahertz vector beams.