FDTD Stimulation Of Light Transmission In Photonic Crystals

The photonic crystal (PC) is a new kind of optics material, which can perfectly control the light transmission. Research of photonic crystal structure is meaningful to fundamental physics and material science. Different optical function devices with great behaviors can be made inside one chip of PC, so the integration level of optical devices will be upgraded to a higher level. So it's application will be widely and important in high speed information processing and data transport fields. We deeply researched the transmission characters of PC wave-guides and PC fibers in this paper.Chapter 1 briefly introduced the PC and the PCF concepts, and their developing background, present developing status respectively, especially about their optical properties, manufacturing methods, and prospective applications.Chapter 2 established the theoretic foundation and analytical mode of this paper. First, we derivate the formula which can calculate the bandgap in PCs by the way of Plant Wave Expansion(PWE). Second the basic model of light transmit in PC is constructed by the way of Finite Difference Time Domain (FDTD). At last, the wave-theory modal of PCF under scalar quantity approximations is presented, and the complete calculation methods and computer programs for the actual analysis are given.In Chapter 3, by the mode we built in chapter 2, we numerically simulate the light broadcasting in PC wave-guides. The result of right angle bend wave-guide shows light broadcast bends with no loss; and the result of PC coupler shows 98% coupler efficiency can be got in the length of 12 periods. These PC devices can be highly integrated. Because of its perfect characters, PC will be greatly used in optical integration fields.In Chapter 4, we established the transmission mode of total reflection PC fiber and by this mode we calculated the PC fiber's electromagnetic field, numerical aperture and dispersion characters. We also simulate some PC fibers of certain parameter. These calculations and analyses are reference to the PCF design.In Chapter 5 we do deep research in the application of PCF, actual applications of PCF are suggested: the full single-mode photonic crystal fiber, large mode area potonic crystal fiber, the broad plant dispersion photonic crystal fiber and high degree of negative dispersion photonic crystal fiber.