Electromagnetic Characteristics of Synthetic Faraday Chiral Media

This paper proposes a new constitutive relation for a synthetic chiral material composed of a large number of small helices embedded in host media. All helical inclusions are arranged with same orientation (e.g., z-direction) and are assumed to have a negligible pitch angle. In other words, the far fields generated by such helices will not produce z-direction components regardless of polarization of incidence waves. Hence, a ferromagnetic-like model is proposed to describe such a synthetic material because the Faraday´s property often exists in the composite helical structure macroscopically behaving like a polycrystalline polymer and the eigenwave consists of two circularly polarized waves with different phase velocity. The characteristics of such a composite material is analogous to that of a magnetized ferromagnetic material, although the results are found that the stronger effect exhibits near the resonant frequency and only a small effect is observed away from the resonant frequency. To predict the constitutive parameters, numerical method is used based on the method of moments combined with the varying illumination algorithm. Cylindrical helix inclusions are used to investigate the effect.