Design And Study Of A Silicon-based Slot Surface Plasmonic Waveguide

In recent years, the characteristics of the surface localization and the near-fieldenhancement for the surface plasmons, make it break through the diffraction limitexisting in the traditional optical waveguide, and transfer and limit light in the sub-wavelength scale. Therefore, it is considered to be the research orientation most likely inachieving optical device miniaturization and highly integration which becomes a researchhotspot at home and abroad. The surface plasmons waveguide structure have sprung up tobe put forward and studied, for that can be used to realize the photoelectric integrated andall-optical integrated. In many surface plasmons waveguide structure, metal-dielectric-metal structure with the characteristics of highly restrictive and simple structure, make iteasier to integrate into the optical circuits. Based on the electromagnetic field theory andsurface plasmons photonics theory, using the finite difference time domain method, thispaper designs and researches a silica-based metal slit surface plasmons waveguide,presents the simulation analysis of the mode field distribution, transmission characteristicsin the subwavelength scale, and the coupling characteristics, and illustrates the advantageof this waveguide structure in the field of the photoelectricity integration.The main content is as follows:Firstly，the paper introduces the basic theory of the surface plasmons. It studies theoptical properties of the metal, describes the excitation mode of the surface plasmons, andanalyzes the transmission characteristics and the dispersion relations, which provides thetheoretic bases for the design and research of surface plasmons waveguide.Secondly, starting from the theory and the numerical simulation, this paper studiesthe electromagnetic distribution and the transmission characteristics of the metal-dielectric-metal surface plasmons waveguide, and introduced the three-dimensional metalslit surface plasmons waveguides based on metal-dielectric-metal waveguide structure.Using the finite difference time domain method, it analyzes the advantages anddisadvantages of this kind of waveguide structure, and puts forward a way to make up itsshortcomings. Finally, this paper proposes a silicon-based trapezoid metal slot surface plasmonswaveguide structure. It is simulated by using finite-difference time-domain method. Thedependence of distributions of electromagnetic field, effective index and propagationlength of the fundamental mode supports by this waveguide on geometrical parameterswere presented. The coupling length，maximum transfer power and crosstalk between twowaveguide structures are studied. The simulation results shows that this kind of waveguidestructure has the more excellent restrictive, the micrometer-scale transmission length, andthe micrometer-scale waveguide separation to avoid crosstalk, to decide that can beapplied in the field of the optical integration and the optoelectronic integration.