An efficient algorithm for modeling photonic crystal fibers

Combining perfectly matched layer (PML) for the boundary treatment, an efficient compact two-dimensional finite-difference time-domain (2-D FDTD) method was introduced to model photonic crystal fibers (PCF). For photonic crystal fibers, if we assume that the propagation constant along the propagation direction is fixed, three-dimensional hybrid guided modes can be calculated by using only a two-dimensional mesh. The computation time and computer memory would be significantly reduced in this way. The numerical results for a triangular lattice photonic crystal fiber are in very good agreement with those from the other theoretical tool and experiment. We also analyze the modal properties of the PCF with air hole deformation. The results show that modal properties of the PCF with air hole deformation in the inner ring of air holes, especially in the first inner ring of air holes, would be affected more than that with air hole deformation in the outer ring of air holes even in the second inner ring of air holes. The compact 2-D FDTD algorithm shows a potential for improving the fabrication technique of PCF efficiently.