Fano effect of metamaterial resonance in terahertz extraordinary transmission

We show that the terahertz resonant transmission through metal hole array can be tailored by filling the holes with metamaterials. Experiment and finite difference time domain simulations show this type of resonant transmission to be induced by locally resonant modes, instead of the usual lateral surface grating mode. As the metamaterial's local resonances can be manipulated by varying their geometric configurations, this type of resonant transmission can be tuned over a broad frequency regime that is subwavelength to the array periodicity, with a transmission profile that can also be tailored by the frequency location of the resonance. Such tunability of resonant transmission, with its attendant enhanced local field intensity in the vicinity of the aperture, may provide some potential applications. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3541652]