A broad-band three-dimensional isotropic left-handed metamaterial

A broad-band three-dimensional (3D) isotropic left-handed metamaterial (LHM) is proposed in this paper. The 3D unit cell is composed of a dielectric cube with metallic Jerusalem crosses on all its six sides. A theoretical model was set up by using equivalent-circuit theory. The magnetic and electric resonant frequencies of the proposed LHM are always equal, which guarantees the existence of a left-handed band. Numerical simulations were carried out to verify the proposed LHM. The results show that the relative bandwidth reaches up to 44.6%; the left-handed band is independent of the polarization of incident waves and is almost the same for different incident angles. Thus, the proposed LHM is a good candidate as a broad-band 3D isotropic LHM.