Numerical parametric study of chiral effects and group delays in Ω element based terahertz metamaterial

In this work, we have systematically studied the impact of geometric parameters on chiral effects which occur in metamaterial made of Ω elements. The analysis of group delays and electric field enhancements indicate stronger interaction between the structure and right circularly polarized waves. Calculations of optical activity and circular dichroism for different values of geometric parameters, allow us to deduce that the thickness of the wire and the gap size have large influence on these effects. On the other hand, the radius of the wire affects mainly the resonant frequency position which enables frequency tunability. The results indicate that multi-functional design of this chiral metamaterial offers great flexibility for various devices: enantiomeric sensors, circular polarizers and light modulators.