ABSTRACT
A fast and cheap, large-area (>1 cm(2)), high-coverage fabrication technique for periodic metallic split-ring resonator metamaterials is presented, which allows control of inner- and outer-ring diameters, gap angles, as well as thickness and periodicity. This method, based on shadow nanosphere lithography, uses tilted-angle-rotation thermal evaporation onto Langmuir-Blodgett-type monolayers of close-packed polystyrene nanospheres. Excellent agreement of the process parameters with a simplified model is demonstrated. Pronounced, tunable optical metamaterial resonances in the range of 100 THz are consistent with simulations.
Subject(s)
Nanospheres/chemistry , Computer Simulation , Nanotechnology/methods , Optics and Photonics , Spectroscopy, Fourier Transform Infrared , Surface PropertiesSubject(s)
Crystallization/methods , Membranes, Artificial , Nanostructures/chemistry , Nanostructures/ultrastructure , Nanotechnology/methods , Nanotubes, Carbon/chemistry , Polystyrenes/chemistry , Adsorption , Coated Materials, Biocompatible/chemistry , Materials Testing , Microspheres , Molecular Conformation , Particle Size , Surface PropertiesABSTRACT
The application of shadow nanosphere lithography for the preparation of large-area, two-dimensional, metallic nanostructures of different shape is described. Through changing the mask morphology by temperature processing and varying the evaporation conditions, particles with morphologies such as rings, rods, and dots have been produced. This process allows outstanding control of the size and morphology of the particles. The efficient technique is shown to scale down the size of metallic nanoparticles from 200 to 30 nm, while preserving the original nanosphere spacing and order. The 150-nm-diameter Fe rings produced by this method show ferromagnetic behavior, which was predicted by theoretical simulation. All the experimental results were confirmed by computer simulations, which also showed the possibility of creating periodic arrays of any other geometrical shape.
