Study Of Terahertz Communication System And Surface Plasmon Waveguide

The history of human communication has been very long. Back to ancient times, people with simple language, murals, etc. to exchange information. To the modern, with the continuing reform of science and technology,communication technology is in a rapid development. The magnitude of information is changing greatly because of the following reasons, such as the development of production, the requirement of massive nature remodeling and the increasing socialization and internationalization of modern production and living. The limitations of existing wire and wireless communications systems in capacity and efficiency are emerging increasingly.Terahertz electromagnetic radiation is one of the last remaining unexplored regions of the electromagnetic spectrum. The THz region, occupying a large portion of the electromagnetic spectrum between the infrared and microwave bands. It has the following features: higher data transfer rate (about 10Gb/s), good direction, higher safety, lower scatter, higher transmittance and so on. THz wave technology can be applied to various scientific fields such as radar, remote sensing, safety inspection, antiterrorism, secure communication, atmospheric/environmental monitoring, real-time biology extraction, medical diagnosis and so on. Now Terahertz technology is becoming a research focus in communication field in developed countriesHigh level of integration is the development direction of modern science and technology. The traditional medium integrated optic components have bottleneck in miniaturization and integration because of the limit of diffraction. Surface plasmons (SPs) are a special kind of electromagnetic field, which are strongly confined to the interface of metal and dielectric materials. Plasmon waveguides can guide optical field in sub wavelength scale, even can break through the diffraction limit. Now it has been the focus of research and hoped to be used in nanometer components and circuit.The main contents and key creation points of this dissertation are as follows:1. We briefly introduced the research situation of terahertz communication domestic and overseas. Analyzed the overall framework of terahertz communication . Gave a review of some key technology in THz communication , and displayed some latest research achievement. We also give a outlook on the developing trend and application prospect of THz wave technology.2. Gave a detailed introduction to surface plasmon and it's characters from solving the Maxwell equations3. We proposed a design of the surface plasmon waveguide, called hybrid nanoline plasmonic waveguide. It consists of a dielectric nanowire separated from a metal nanoline by a nanoscale dielectric gap. The coupling between the plasmonic and waveguide modes across the gap allows effective sub wavelength transmission in non-metallic regions. In this way the hybrid mode can be strongly confined to sizes as small as 1/600 of the area of a diffraction limited spot4. Introduced a high refractive index dielectric core into the channel plasmon waveguide which will allow us to confine most of the energy within it, because of the low loss constant compare to metal, the mode propagation length of our structure can be at least 2 times longer than that of the traditional channel waveguide.5. We studied the optical properties of the metal nanoparticle, metal nanoparticle with dielectric shell, and the metal nanoshell respectively with Mie theory. Based on the theory of stimulated emission of surface Plasmon assisted by gain materials, we give a feasible solution that add the gain materials to both dielectric materials in and out of the metal shell, so the metal nanoshell particle can give a stimulated emission, and the emission wavelength can be designed from 600nm to 1000nm by change the shell size and thickness.