Dual- and Multiband Chiral Metamaterial Structures With Strong Optical Activity and Negative Refraction Index

A novel dual-band chiral metamaterial based on the conjugated gammadions structure is proposed. Simulation and experimental results, which are in a very good agreement, indicate that the proposed structure exhibits giant optical activity and a negative refractive index for right and left circularly polarized waves due to its strong chirality in two near frequency bands. The results show that the effective frequency bands of this structure are independent and can be simply adjusted using the presented design curves. Furthermore, our studies prove that generalization for the multiband chiral metamaterials is possible.