Left-handed material containing spherical and nonspherical metallic and magnetic particles

Abstract

We investigate a composite medium consisting of two types of dispersive particles. By invoking the effective medium approximation both the effective permittivity and permeability are derived separately in the limit of the long wavelength, and thus the effective refractive index can be obtained. We realize the left-handed property of the composite characterized by the negative effective index through the suitable control of the volume fraction. Then, we pay attention to the effective refractive index of the composite material consisting of two components with different shape in the low frequency limit. Numerical results show that the shape of granular inclusions has a large influence on the effective refractive index, and the oblate ellipsoid will be more useful for preparing the left-handed material than the spherical one. Moreover, by adjusting the shape of granular inclusions, a transition of the material properties between the left- and right-handed can be realized.