Dual-polarity plasmonic metalens for visible light

Surface topography and refractive index profile dictate the deterministic functionality of a lens. The polarity of most lenses reported so far, that is, either positive (convex) or negative (concave), depends on the curvatures of the interfaces. Here we experimentally demonstrate a counter-intuitive dual-polarity flat lens based on helicity-dependent phase discontinuities for circularly polarized light. Specifically, by controlling the helicity of the input light, the positive and negative polarity are interchangeable in one identical flat lens. Helicity-controllable real and virtual focal planes, as well as magnified and demagnified imaging, are observed on the same plasmonic lens at visible and near-infrared…

• AW
  Advantage West Midlands
• EC
  European Commission
• NU
  National University of Singapore

  Award: R-263-000-688-112
• NN
  National Natural Science Foundation of China

  Awards: 61161130005, 11004119
• CS
  China Scholarship Council
• ER
  European Regional Development Fund