Modal contrast engineering in ultraviolet and visible metalenses enabled by material-selective hybridization

Metasurfaces enable ultrathin optics through nanoscale light control, yet extending high-efficiency operation from the ultraviolet (UV) to visible has been constrained by material and design limitations. Here, we present a material-selective hybrid metalens platform in which a structurally invariant SiO₂ skeleton is conformally coated with nanometer-thick oxide layers, producing high-efficiency metalenses in distinct spectral windows without geometric modification. Low-temperature atomic layer annealing at 80 °C crystallizes TiO₂ to raise its refractive index for visible operation while preserving amorphous ZrO₂ for UV transparency. Ultrathin coatings establish the modal birefringence required for polarization conversion, yielding average efficiencies of 69% (250-400 nm) and 75% (400-700 nm), with diffraction-limited focusing across the bandwidth. We demonstrate a compact real-scene UV camera revealing sunscreen coverage, authentication markers, and biological structures for dermatology, materials inspection, and forensics, alongside a lightweight full-color virtual-reality eyepiece. These results establish hybrid metasurfaces as scalable, manufacturing-compatible alternatives to bulky refractive optics.