New types of left-handed materials based on the Z-shaped metal structure

Based on a Z-shaped metal structure, two new types of left-handed materials (LHMs): LHM with units of off-plane anti-symmetric Z-shapes (OPAZ) and LHM with units of in-plane orthogonal Z-shapes (IPOZ) are proposed. In the OPAZ LHMs, the double-negative left-handed band is proved to be in the range from 9.35 GHz to 10.67 GHz by extracting effective permittivity and permeability from the simulated scattering parameters. While in the IPOZ LHMs, it finds the left-handed band is between 5.193 GHz and 5.617 GHz. The numerical study shows that the OPAZ LHMs exhibits a broader left-handed band with simpler configuration, and it is easier to be fabricated. The IPOZ LHMs do means a relatively narrow left-handed band, but it possesses an attractive advantage of 2D left-handedness, which means the LHMs could show a left-handed band without any limitation on the direction of k-vector as long as the H-field is perpendicular with the substrate plane. This property of left-handedness isotropy is of great significance in real-world application.