Eur. Phys. J. B (2012) 85: 62
https://doi.org/10.1140/epjb/e2011-20773-9

Regular Article

Broadband 3D isotropic negative-index metamaterial based on fishnet structure

Department of Electronic Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, P.R. China

^a e-mail: nieyan@mail.hust.edu.cn

Received: 20 September 2011
Received in final form: 18 November 2011
Published online: 13 February 2012

Abstract

In this paper, we numerically demonstrate a broadband 3D isotropic negative index metamaterial (NIM) at microwave frequency ranges, which is composed of double periodic array metallic fishnet structure (FS) etched on the six sides of a cubic dielectric substrate. The electric and magnetic L-C resonance circuit models are constructed to demonstrate the broadband resonance properties of the proposed 3D metamaterial. The finite integration technology (FIT) simulation and standard S parameters retrieval methods are used to calculate and analyze the negative characteristics, isotropy and polarization of the 3D model. The numerical results show that the negative index bandwidth is about 7 GHz and relative bandwidth can be up nearly to 63%, the negative-index pass band is independent of the polarization of incident waves and is almost the same for different oblique incident angles. Thus, the proposed metamaterial is good candidate as a broad-band 3D isotropic NIMs.