Simple Method for Prediction of Far-Field Patterns of Single-mode Dispersion-shifted and Dispersion-flattened Fibers

Abstract

Based on the simple series expression of fundamental mode in dispersion-shifted and dispersion-flattened fibers, we formulate analytical expressions for far-field pattern of such fibers and evaluate them. The concerned calculations require much less computations. Taking three typical trapezoidal fibers as example of dispersion-shifted fiber, we show that our results match excellently with the exact numerical results. As example of dispersion-flattened fiber, we choose two parabolic profile W and two step profile W fibers for our study and here also, our estimations agree excellently with the exact numerical results. The present formalism can also be used for predicting different propagation characteristics associated with the far-field. Further, one can also predict the fundamental modal field from the knowledge of far-field pattern. This simple but accurate formalism developed will benefit the system engineers working in the field of optical technology.