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IEEE Journal of Lightwave Technology
Volume 18 Number 7, July 2000

Table of Contents for this issue

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Three-Dimensional Electromagnetic Modeling of Fiber-Core Effects on the Coupling Characteristics of Weakly Fused Tapered Fiber-Optic Couplers

Tzong-Lin Wu Member, IEEE

Page 1024.

Abstract:

Based on the full-wave formulations, which combine the finite element method and the boundary element technique, and the step-like approximation method, a three-dimensional (3-D) electromagnetic modeling approach is proposed in this work to investigate the fiber-cores effects on the coupling characteristics of the weakly fused tapered couplers. We find the fiber cores have significant effects on the mode field patterns, coupling coefficients, and birefringence for the coupler with large normalized frequencies. The influence of the fiber cores on the coupling behavior for the real couplers, such as 3 dB power dividers,polarization beam splitters, and wavelength demultiplexing/multiplexing couplers,are also studied in 3-D view. It is found that the effects of fiber-cores in the weakly fused tapered couplers have to be considered for accurately modeling their coupling behavior, although the model with no-core assumption can predict the trend of the coupling characteristics for the real couplers.

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