Comparison of compact electric-LC resonators for negative permittivity metamaterials.

Various easy made planar electric meta-atoms are presented as alternative designs to the conventional electric-LC resonator for achieving negative permittivity. Transforming the LC topology of the resonator helps to facilitate transposition of geometrical parameters for the optical regime and also to improve the metamaterial homogeneity. Our approach aims to simplify the resonator design and achieve a lower resonance frequency without being limited by fabrication techniques. A parametric sweep is performed to evaluate the influence of the different geometrical parameters on the resonance frequencies of the meta-atoms. The electromagnetic behavior is investigated through both simulations and experiments in the microwave regime. Our results show that the developed meta-atoms exhibit a purely strong electric response to normally incident radiation and can be used very effectively in producing materials with negative permittivity. For instance, a Z-shaped structure is shown to present a higher effective medium ratio. The proposed meta-atoms can find various applications in planar high-frequency passive circuits due the simplicity of fabrication. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2287-2295, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27050 [ABSTRACT FROM AUTHOR]