Article

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.

Full-text

Available from: Antonio I. Fernández-Domínguez, Jun 13, 2015
0 Followers
 · 
104 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A single groove in a parallel-plate waveguide (PPWG) has been applied to a tunable terahertz (THz) notch filter with a transverse-electromagnetic (TEM) mode. When the air gap between the metal plates of the PPWG is controlled from 60 to 240 μm using a motor controlled translation stage or a piezo-actuator, the resonant frequency of the notch filter is changed from 1.75 up to 0.62 THz, respectively. Therefore, the measured tunable sensitivity of the notch filter increases to 6.28 GHz/μm. The measured resonant frequencies were found to be in good agreement with the calculation using an effective groove depth. Using a finite-difference time-domain (FDTD) simulation, we also demonstrate that the sensitivity of a THz microfluidic sensor can be increased via a small air gap, a narrow groove width, and a deep groove depth.
    Optics Express 12/2012; 20(28):29605-12. DOI:10.1364/OE.20.029605 · 3.53 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We describe a fast method to evaluate the far-field profile of a generic planar disposition of plasmonic gratings and slit apertures, based on the ideal decomposition of the structure into a linear array of distinct scattering elements and provided an accurate description of their plasmonic and radiating behaviors. This approach allows for a fast calculation of the irradiation diagram, and has general validity for any kind of surface defects and for multiple set of gratings and slit apertures.
    Journal of the Optical Society of America B 04/2015; 32(4). DOI:10.1364/JOSAB.32.000676 · 1.81 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Due to their long propagation length at a metal surface in the far infrared, surface plasmons make potentially feasible the design and realization of 2D integrated terahertz systems over a metallic substrate. In this article, we present a review of recent works dedicated to surface plasmon properties on structured metallic surfaces. We study excitation, propagation, diffraction and reflection of terahertz surface plasmon on shallow gratings and of spoof plasmons on deep sub-wavelength structures. The analysis of the experimental data supplied by terahertz time-domain spectroscopy allows us to point out the main parameters that govern this diffraction process and the propagation of a surface plasmon over a flat or corrugated metal surface. KeywordsSurface plasmon–Terahertz time-domain spectroscopy–Diffraction grating–Metal structure
    Journal of infrared, millimeter and terahertz waves 10/2011; 32(10):1054-1073. DOI:10.1007/s10762-011-9814-5 · 1.89 Impact Factor