Hybrid SRRs Design and Fabrication for Broadband Terahertz Metamaterials

Hybrid metamaterials comprising split-ring resonator (SRR) structures with different gap dimensions are fabricated on polyethylene naphthalate (PEN) films by parallel laser micro-lens array (MLA) lithography and a liftoff process. The unit cell of hybrid metamaterials consists of four SRRs with the same SRR core side length but different gap sizes. The different-gap-size SRRs in each unit cell correspond to different but successive resonance dips, which are coupled to form a significantly broader band with enhanced resonance. The hybrid SRRs design is numerically and experimentally demonstrated, showing a much broader bandwidth to cover all narrowband induced by each SRR and enhanced resonance as compared with a uniform SRR design.