Caracterización de medios quirales utilizando ondas con polarización circular

Abstract

The characterization of metamaterials is usually carried out by illuminating a sample with a linearly polarized plane electromagnetic wave. In points far from the sample, sensors are introduced to measure the transverse components of the field, before and after the sample, in order to compute the reflection and transmission coefficients related with the coand cross-polar field components. Based on this information, retrieval algorithms allow parameters like rotation angle, effective chirality, refraction index, etc., to be calculated. Here we obtain information only on the transmission signals under illumination with plane circularly polarized waves, from which chirality and the rotation angle due to the electromagnetic activity of the material can be directly calculated. The method, which allows a simpler characterization of the metamaterial slab under study, is applied to the study of simulated chiral metamaterials composed of a dielectric slab substrate with a periodic array of metallic inclusions. The findings are contrasted with the experimental results obtained with linear polarization irradiation.