Two-Photon and Multiphoton Fabrication of Photopolymer Metasurfaces: Subwavelength Feature Control, Dispersion and Device Efficiency

Photopolymer metasurfaces require manufacturing control at a scale where unit-cell geometry, material dispersion and collective optical response are inseparable. This review examines two-photon and multiphoton fabrication as a route to three-dimensional or high-aspect- ratio metasurface architectures, with emphasis on subwavelength feature fidelity, resonator-to-resonator variability, refractive-index state and efficiency. General two-photon process physics provides necessary context, but metasurface qualification additionally requires device-specific evidence linking fabricated meta-atom dimensions to phase, amplitude or polarisation response. The review distinguishes local feature resolution from array-level registration and from optical efficiency, because a process can resolve isolated structures while failing through accumulated dimensional bias or disorder. A practical qualification route is proposed using dimensional distributions, dispersion-aware electromagnetic comparison, efficiency and wavefront measurements, and stability tests that preserve the distinction between fabrication error and material-state drift.

ER-332 · Version 0.4.