Analysis of Double Layer Cross Strips with Chiral Configuration Exhibiting Negative Refractive Index

Abstract

Metamaterials composed of metallic strips on both side of the substrate are analyzed at microwave frequencies. The rectangular shaped metallic foils are rotated by 90o with respect to their adjacent metal strip on each side of the substrate. The twist angle between the cross strips on opposite sides of substrate is 40o. The proposed structure exhibits the properties of chiral medium such as optical activity and circular dichroism due to their cross coupling between the electric and magnetic fields. The rectangular shaped chiral objects can be easily fabricated on double side substrate. Both transmission and reflection resonances are illustrated. The chiral configuration of this metamaterial structure is analyzed in commercial software Computer Simulation Technology (CST) microwave studio and negative refractive index is observed. Moreover, other electromagnetic structural parameters such as chirality, optical activity and polarization effect are discussed.