Bragg reflection of terahertz waves in plasmonic crystals

Division of Electrical and Electronics Engineering, Korea Maritime University, Busan 606-791, Korea.
Optics Express (Impact Factor: 3.53). 06/2009; 17(11):9212-8. DOI: 10.1364/OE.17.009212
Source: PubMed

ABSTRACT We present experimental and theoretical studies on terahertz surface plasmon (TSP) propagation on slit and rectangular aperture arrays in an aluminum sheet. Terahertz waves are coupled onto the plasmonic structures via a parallel plate waveguide. Long-lasting oscillations are observed in the temporal pulse shape after propagating through the periodic structure, whose Fourier transformation into the frequency domain results in Bragg-resonance spectral features. We show that the interference between the incident wave and the radiation reflected from both the aperture array and the waveguide block is responsible for this Bragg-resonance behavior. The reflection coefficient for a single slit is deduced to be 0.017 +/- 0.002.


Available from: Antonio I. Fernández-Domínguez, Jun 13, 2015
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