Optical nano-woodpiles: large-area metallic photonic crystals and metamaterials

摘要: Metallic woodpile photonic crystals and metamaterials operating across the visible spectrum are extremely difficult to construct over large areas, because of intricate three-dimensional nanostructures sub-50 nm features demanded. Previous routes use electron-beam lithography or direct laser writing but widespread application is restricted by their expense low throughput. Scalable approaches including soft lithography, colloidal self-assembly, interference holography, produce structures limited in feature size, material durability, geometry. By multiply stacking gold nanowire flexible gratings, we demonstrate a scalable high-fidelity approach for fabricating metallic crystals, with down 10 nm produced bulk at cost. Control sequence, asymmetry, orientation elicits great control, visible-wavelength band-gap reflections exceeding 60%, strong induced chirality. Such stretchable architectures can refractive index near zero, easily tuned IR ranges.