Vector analysis of dispersion for the-fundamental cladding mode in photonic crystal fibers

The dispersions of the fundamental cladding mode in photonic crystal fibers( PCFs) are computed with a vectorial effective index approach in this paper. By comparing with the results obtained from biorthonormal-basis method or scalar effective method, it is found that the results of this paper are in accordance with that obtained from the biorthonormal-basis method, and that the scalar effective method is a good approximation at a lower air-filling fraction or higher normalized wave-number A/A. For high accuracy at larger air-filling fraction or lower normalized wave-number A/A it is necessary to consider the vectorial method. The relation between effective index of cladding and microstructure of PCFs is discussed. The computation and analysis in this paper can provide a theoretic reference for designing of PCFs.