ACCURATE FINITE-ELEMENT ANALYSIS OF DUAL-MODE HIGHLY ELLIPTIC-CORE FIBERS

A scalar finite-element method is used for investigating propagation c haracteristics of dual-mode highly elliptical-core fibers. The dispers ion property, polarization modal birefringence, and spatial modal bire fringence are calculated. To improve the accuracy of solutions, isopar ametric curvilinear elements are introduced. The applicability of the scalar finite-element method for highly elliptical-core fibers is asse ssed by comparing the results obtained with the vector finite-element method. An approximate simple approach, in which an elliptical-core is replaced by an appropriate rectangular-core, is also examined.