A full-vectorial FDFD analysis of photonic crystal fibers

A full-vectorial finite-difference frequency domain (FDFD) method is used to analyze the photonic bandgaps and the mode fields of photonic crystal fibers (PCFs) with different structures. As a new kind of developed fibers with many particular and useful characteristics, PCFs have recently attracted a great deal of interest both in theory and experiments, and many modeling techniques have been applied to describe their characteristics. It has been proved that the full-vectorial FDFD method can achieve an accurate and stable analysis on the fantastic features of the PCF, by which the photonic bandgaps and the mode fields can be simply calculated first. The bandgap scan map of the triangular structure with the change of holes diameters has been proposed. And the bandgap maps of the 2D triangular lattice with and without defects are compared, too. Furthermore, the numerical results for 2D TE modes in the two dimensional triangular lattice with defects have been presented, where the air holes are circle and hexagon, respectively. The latter structure brought forward by us proves to be fit for the gas sensors. Based on the photonic bandgaps and the mode fields of the PCF, several other useful features can be calculated for the later analysis of the fibers.