الفهرس 
Chapter (1) IntroductionOnly 14 pages are availabe for public view
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Abstract
As a typical sized electronic device approaches the nanometer range, it is difficult for the technology integrations on a single chip to match the size of these device and optical components. For conventional dielectric waveguides, because of the diffraction restriction the mode cannot be confined to sizes less than half the wavelength. The so-called surface plasmon polaritons (SPPs) are possible and promising technological development to resolve that problem. With optical plasmonic becoming more and more important for a broad range of applications, it is essential to formulate a model that is physically comprehensible direct-ly. Metals have a complex permittivity in the optical regime, which means that SPPs have a large propagation loss. SPP based waveguides suffer from huge propagation loss, and low propagation length because of the intrinsic ohmic loss. In the present thesis, two designs of hybrid plasmonic waveguide are suggested and simulated using COMSOL multiphysics software package. A comparative analysis between these two suggested plasmonic waveguide and the previous verified work is also shown in the presented thesis. For the first design, a new design of hybrid plasmonic photonic crystal (PhC) wave-guide is proposed and analyzed at operating wavelength of 1550 nm. The suggested design consists of hybrid cylindrical core with periodic grating as a cladding region. The effective index (neff), propagation length (Lp), and normalized mode effective area (Aeff) of the sup-ported modes are numerically investigated using full vectorial finite element method. The cladding geometry is tuned to obtain long propagation length with good field confinement. The reported plasmonic PhC with uniform grating achieves long propagation length and low propagation loss of 124 µm, and 0.035 dB/µm respectively. Further, the PhC with chirped cladding offers propagation length and low propagation loss of 162 µm, and 0.0268 dB/µm at λ=1550 nm, respectively. The second proposed design is graphene-based hybrid plasmonic waveguide that is proposed and analyzed to improve the propagation length with a good confinement. The suggested design has a silica rectangular waveguide between GaAs cylindrical dielectric waveguide and multilayer-graphene-based coated substrate. Through the numerical study, the mode characteristics including the effective index (neff), propagation length (Lp), nor-malized mode area (Aeff) of the supported modes are numerically investigated using full vectorial finite element method. Further, the geometrical parameters of the proposed design are tuned to obtain long propagation length. The numerical results show that long propaga-tion length of 171.6 µm at frequency of 3THz is achieved at mode normalized area of ” ” ” ” " ~ " ” ” ” ”10-3λ2 and propagation loss of 0.0253dB/µm. Therefore, the reported waveguide shows a strong confinement with low propagation loss.