Title :
Finite-Difference Modeling of Dielectric Waveguides With Corners and Slanted Facets
Author :
Chiou, Yih-Peng ; Chiang, Yen-Chung ; Lai, Chih-Hsien ; Du, Cheng-Han ; Chang, Hung-chun
Author_Institution :
Dept. of Electr. Eng., Nat. Taiwan Univ., Taipei, Taiwan
fDate :
6/15/2009 12:00:00 AM
Abstract :
With the help of an improved finite-difference (FD) formulation, we investigate the field behaviors near the corners of simple dielectric waveguides and the propagation characteristics of a slant-faceted polarization converter. The formulation is full-vectorial, and it takes into consideration discontinuities of fields and their derivatives across the abrupt interfaces. Hence, the limitations in conventional FD formulation are alleviated. In the first investigation, each corner is replaced with a tiny arc rather than a really sharp wedge, and nonuniform grids are adopted. Singularity-like behavior of the electric fields emerge as the arc becomes smaller without specific treatment such as quasi-static approximation. Convergent results are obtained in the numerical analysis as compared with results from the finite-element method. In the second investigation, field behaviors across the slanted facet are incorporated in the formulation, and hence the staircase approximation in conventional FD formulation is removed to get better modeling of the full-vectorial properties.
Keywords :
finite difference methods; optical waveguide theory; dielectric waveguide; finite-difference modeling; full-vectorial property; nonuniform grid; quasistatic approximation; slant-faceted polarization converter; staircase approximation; Corners; dielectric waveguides; finite-difference method (FDM); frequency-domain analysis; full-vectorial; singularities; step index; tiny arcs;
Journal_Title :
Lightwave Technology, Journal of
DOI :
10.1109/JLT.2008.2006862