Title :
On the validity of the effective-index method for rectangular dielectric waveguides
Author :
Lee, Jae-Seung ; Shin, Sang-Yung
Author_Institution :
Dept. of Electr. Eng., Korea Adv. Inst. of Sci. & Technol., Seoul, South Korea
fDate :
8/1/1993 12:00:00 AM
Abstract :
The effective-index method (EIM) for rectangular dielectric waveguides is derived as an approximation from an exact equivalent-network formulation. It is explained why EIM gives accurate results for the fundamental modes in near cutoff region as well as for all the guided modes in well-guiding region. As a direct improvement on EIM a simple eigenvalue equation is presented, which takes into account the shape of the predominant slab-waveguide mode. It is shown that EIM overestimates propagation constants compared to the improved results
Keywords :
eigenvalues and eigenfunctions; integrated optics; optical constants; optical waveguide theory; rectangular waveguides; refractive index; effective-index method; eigenvalue equation; exact equivalent-network formulation; fundamental modes; guided modes; near cutoff region; predominant slab-waveguide mode; propagation constants; rectangular dielectric waveguides; well-guiding region; Dielectrics; Eigenvalues and eigenfunctions; Equations; Optical network units; Optical waveguides; Propagation constant; Rectangular waveguides; Shape; Slabs; Waveguide junctions;
Journal_Title :
Lightwave Technology, Journal of
