Numerical investigation on metamaterial side of epoxy resins at visible light

Metamaterials are composite materials whose material properties (acoustic, electrical, magnetic, optical, etc.) are determined by their geometrical structure, especially the unit cells. The development of metamaterials... [ view full abstract ]

Metamaterials are composite materials whose material properties (acoustic, electrical, magnetic, optical, etc.) are determined by their geometrical structure, especially the unit cells. The development of metamaterials continues to redefine the boundaries of materials science. These materials offer excellent design flexibility with their customized properties and their tunability.

The proposed structure in this paper is made from epoxy resins nanospheres. Each nanosphere has a radius of 20nm. The structure was modeled in CST suite studio along the frequency range 430-700THz. The results showed that this structure has both negative refractive index and extremely high refractive index. It also showed that all of the parameters permittivity, permeability and refractive index have negative values along the frequency range 430-597THz which cover the colors red, orange, yellow and green. In addition it has almost unitary transmission for those colors which make the structure useful in the lens industry. The frequency 597THz would be considered as a frequency shift between very low refractive index and very high refractive index. The structure showed an excellent transmission of the light with zero absorption and weak reflection. After that the effect of the radius were studied. The results showed that increasing the radius of the spheres make the refractive index move towards positive values, with the same result applied on epsilon and mu, in addition to a small value of imaginary part for that wavelength.