Optically thin terahertz metamaterials

School of Electrical and Computer Engineering, Oklahoma State University, Stillwater, Oklahoma 74078, USA.
Optics Express (Impact Factor: 3.49). 05/2008; 16(9):6537-43. DOI: 10.1364/OE.16.006537
Source: PubMed


Resonant properties of optically thin metamaterials are studied by terahertz time-domain spectroscopy. Both the lower energy inductor-capacitor (LC) and the higher energy dipole resonances of the planar double split-ring resonators (SRRs) exhibit characteristic evolution with various sub-skin-depth thicknesses of the constituent Pb film. The signature of the LC resonance begins to emerge at a critical thickness near 0.15 skin depth. The resonances reveal a characteristic enhancement; they are strengthened remarkably with increasing SRR thicknesses at sub-skin-depth level and then gradually saturate beyond the skin depth.

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