Analysis of chiral effects in non-planar metamaterials with oblique incidence

Abstract

One of the main research lines of the Grupo de Electromagnetismo of the Universidad de Cantabria is focused on the study and characterization of planar chiral metamaterial (CMM) structures implemented on printed circuit board technology. The objective of this communication is to analyze the influence of the angle of incidence on the chiral behavior of metamaterial structures. A variation of the split ring resonator (SRR) particle has been used as unit cell of the periodic metamaterials analyzed. From this structure, the effect of the angle of incidence on the chiral response is analyzed, evaluating variations in the geometry that provide different types of interaction between unit cells or between the incident wave and the structure. The SRRs are printed only on one side of the printed circuit board. Fig.1. This way, with normal incidence the structure is achiral.

The obtained results show that the angle of incidence is a key parameter for the structure in order to present a chiral behavior. In this case, the chiral behavior is shown as a high difference between the transmission levels of the two eigenwaves (left handed and right handed circular polarized waves), i.e., circular dichroism.