Polarization‐Controlled Multifunctional Metasurfaces for Ultraviolet‐Visible Dual‐Band Imaging

Abstract Metasurfaces have emerged as a rapidly advancing technology enabling easy‐to‐integrate planar photonic devices, owing to their exceptional control of light‐matter interaction at a subwavelength scale. They offer unique optical functionalities for various applications, including medical imaging. Despite their early successes, fixed capabilities and narrow operational bandwidths limit their integration into advanced chip‐scale photonic systems. Addressing the need for ultra‐compact, high‐performance UV–Vis imaging tools in microscopic and bio‐imaging, a band gap‐engineered silicon nitride‐based polarization‐controlled, single‐cell‐driven, dual‐band (UV–Vis) all‐dielectric imaging platform is developed. This platform integrates multiple optical effects through a single metasurface, utilizing the spatial symmetry of localized fields within the nanoresonator. This design leverages the holographic principle and polarization decoupling effect to simplify the complexity of broadband/dual‐band metasurfaces. To validate the design, a multifunctional metalens, and a meta‐vortex plate, demonstrating efficient structuring of UV–Vis light, is developed. Supported by rigorous numerical and experimental investigations, this work marks a significant advancement in UV–Vis imaging technologies, setting a new standard for medical diagnosis, disease prognosis, and clinical technology innovation. It is envisioned that broadband, multifunctional imaging devices are becoming a next‐generation platform across interdisciplinary frontiers.