用FDTD法计算光子晶体探析

Analysis on Photonic Crystal with FDTD

基于电磁场时域有限差分法(FDTD)来计算光子晶体(PC)的方法,较为详细的分析了在运用FDTD方法时,需要注意的一些问题,尤其是关于其晶格位置以及晶格上各个电磁场分量的分布和完全匹配层(PML)中在边界处其电磁场的处理;以此为理论依据分析了PC在作为光波导时其电磁场的变化。在入射光的波长、晶格常数、元胞半径不同时对传播损耗的影响,在波长一定时,晶格常数过大或过小都会导致光在光子晶体中的损耗过大,为光子晶体作为光滤波器或其他器件的设计提供了参考和理论计算的方法。

Based on Finite Difference Time Domain （FDTD） method to compute the modefield of Photonic Crystal （PC）. Analyzed some problems by using FDTD, especially the distribution of mesh and set to the properties of PML. With FDTD method solve Photonic Crystal waveguide. Designed a wavelength filter in optical communication system,and the effect of PC structure parameters （lattice constant,cell＇s radius ）is discussed. When the wavelength is constant. The influence of these pa rameters are mainly decided the dift＇erence of lattice constant. So it can control the light transmission in the medium. Proved that the Photonic crystal has great prospect in optical communication systems,also can apply in other domains.