Flexible, low-loss, large-area, wide-angle, wavelength-selective plasmonic multilayer metasurface

Flexible, low-loss, large-area multilayer plasmonic optical metasurfaces are demonstrated and analyzed that provide wavelength-selective reflectance >95% and transmittance <1% with low absorption and robustness to variation in angle of incidence and polarization. These characteristics are shown to be insensitive to vertical misalignment between layers, and defects within individual layers. Analysis based on analytical modeling and numerical simulations provides physical insights into reflectance, loss, and bandwidth of these multilayer metasurface structures. Fabry-Perot resonances associated with phase shifts from each individual metasurface are also examined, and evidence of m ¼ 0 resonance due to the nonzero, wavelength dependent phase shift from the metasurface cavity is demonstrated and explained. Finally, fabrication on flexible substrates via rapid, large-area nanosphere lithography, and the robustness of optical properties of interlayer misalignment together enable the demonstration of wavelength-selective focusing at optical frequencies.