Title :
Wideband Slow Surface Plasmons in Double Resonator Plasmonic Grating Waveguide
Author :
Zafar, Rukhsar ; Salim, Mohammad
Author_Institution :
Dept. of Electron. & Commun. Eng., Malviya Nat. Inst. of Technol., Jaipur, India
Abstract :
We propose a theoretical and numerical investigation of surface plasmon polaritons supported by a metal- insulator-metal (MIM) waveguide, periodically coupled to a series of adjacent resonators. The slow light characteristics of the MIM-coupled resonator is analyzed by controlling separation or displacement between resonators. By tailoring this displacement factor, group velocity of slow wave structures is reduced to a great extent with a large value of the normalized delay bandwidth product (NDBP = 0.667) that measures the capacity of the device. A low value of group velocity (Vg = c/7) is reported over an ultralarge bandwidth (Δf = 21 THz). An unusual U-shaped group index-frequency curves with a constant group index ng is obtained, which leads to a nearly-zero value of group velocity dispersion followed by positive and negative peaks. The structure is also analyzed for changing the depth of the resonators. The structure can be further modified to suit different applications in optical switching device, dispersion compensating units, and nonlinear optics devices.
Keywords :
MIM structures; diffraction gratings; optical couplers; optical delay lines; optical dispersion; optical resonators; optical waveguides; plasmonics; polaritons; refractive index; slow light; surface plasmon resonance; MIM-coupled resonator; U-shaped group index-frequency curves; dispersion compensating unit applications; displacement factor; double resonator plasmonic grating waveguide; frequency 21 THz; group velocity dispersion; metal- insulator-metal waveguide; nonlinear optics device applications; normalized delay bandwidth product; optical switching device applications; slow wave structures; wideband slow surface plasmon polaritons; Bandwidth; Dispersion; Indexes; Optical resonators; Optical waveguides; Plasmons; Slow light; Surface plasmon polaritons; group velocity; metal??insulator??metal; normalized delay-bandwidth product;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2014.2350514