Characterization of metamaterials

Abstract

Characterization is a fundamental issue on metamaterials (MTM) science due to the possibility of modulating properties as permittivity, permeability, and refraction index. According to this, MTM can be classified in four main categories depending on their magnetics and dielectric properties: double positive, epsilon negative, mu negative and double negative materials. Depending on their applications, MTM can be also sorted as artificial dielectrics, artificial magnetics, chiral, plasmonic, omega shape and tunable materials, among others. To achieve the required attributes, complex matrices employing diverse substances must be assessed, applying theoretical design parameters. The response of the developed MTM must attend to a specific parameter as temperature or frequency. MTM matrix properties are not proportional to individual constituents, therefore, different characterization techniques are employed to retrieve of MTM parameters, including resonator, free-space, waveguide, S-parameter and Nicolson-Ross-Weir method. The most suitable technique selection depends on material, operation frequency range, temperature, accuracy, and sample size and thickness. The main uses for metamaterials are waveguides, sensing, super lens, cloaking, absorbers, energy harvesting devices, antenna and antenna elements.