Orthogonally twisted planar concentric split ring resonators towards strong near field coupled terahertz metamaterials

We present strongly coupled planar terahertz metamaterials in which the metamolecule design comprised two concentric split ring resonators (SRRs) with their capacitive gaps oriented orthogonally in order to establish strong near field coupling. Experimental results clearly demonstrate huge splitting in the fundamental inductive-capacitive resonance when the incident terahertz polarization couples to the metamolecule system through the outer SRR. However, the strengths of split resonances are too weak to detect experimentally when the meta-molecule system is excited through the inner SRR. Such strongly coupled metamolecules can enable additional dispersion tuning and polarization control in metamaterials.