Research On Band-Gap Characteristics And Spectrum Control And Regulation Of Two-Dimensional Photonic Crystal

Photonic crystal (PC), widely researched in recent years, is a new developing optical material, which has been researching hotspot in multiple disciplines, especially in electronic computer and photo-communication areas. On the basis of electromagnetism, optics, solid state physics theory, the author analyzed photonic band gap (PBG) and spectrum control and regulation characteristics in detail.In this dissertation, PBG distribution in two-dimensional rectangular-lattice and hexagonal-lattice PC with column structure has been calculated based on solid-band theory and plane wave expansion method. According to electromagnetism theory, the author analyzed field-quantities variation while the electromagnetic wave traversing through two-dimensional dielectric column, obtained transmission characteristics of electromagnetic wave traversing dielectric medium whose permittivity changed with spatial orientation, and discussed PC applications in optical waveguide and solar thermo-photovoltaic (TPV) areas.1. Plane-waveguide characteristics of rectangular lattice was calculated using finite-difference time-domain method. The author investigated the influence of waveguide width towards superior-limit wavelength of passband, and analyzed the variation of field quantities and transmission power. A suppose of the application of PC waveguide was put forward together.2. The author introduced the method of two-dimensional PC design based on the variation law of band gap in PBG materials along with permittivity and structural parameters. A PC film with hexagonal lattice using gallium arsenide was proposed, and the transmission characteristics were separately analyzed in lossy and lossless medium.3. Spectrum radiation characteristics of two multilayer-film radiators, separately made of tungsten and silver, were analyzed and compared in this dissertation. Two multilayer-film optical filters separately with (1/2LH1/2L)n and (LH)n structures were proposed to control and regulate the spectrum received by TPV cell. The author also investigated the influence of PC radiator and filter towards the spectral efficiency of TPV system. The results showed that PC spectrum-transmission characteristics could improve heat-flux distribution of radiation spectrum, and enhance the energy conversion efficiency of solar TPV system.