Application of media with a negative refractive index in IR and visible frequencies

The paper is mainly concerned with the study of negative refraction phenomenon dependent on the incident light frequency in 2D photonic crystal which consists of a hexagonal lattice of circular dielectric rods with Si. The result indicates that along with the accretion of incident light frequency, the angle of refractive light and negative refractive index in absolute terms become smaller gradually. This law offers an application of differentiating two close incident light frequencies. And a sample has been made successfully to realize negative refraction phenomenon.