Computing the eigenmodes of lossy field-induced optical waveguides

Author

Coalson, Rob D. ; Pant, Dhruv K. ; Ali, Arshad ; Langer, Dietrich W.

Author_Institution

Dept. of Chem., Pittsburgh Univ., PA, USA

Volume

12

Issue

6

fYear

1994

fDate

6/1/1994 12:00:00 AM

Firstpage

1015

Lastpage

1022

Abstract

Slab waveguides which achieve lateral confinement in the guiding region by applying a spatially selective electric field across a multiquantum well cladding region are modeled by solving the appropriate Helmholtz equation. Attention is focused on the effects of absorption in the cladding region of the waveguide, which leads to attenuation along the propagation direction. Galerkin´s method is utilized to compute exact mode propagation constants and intensities of the fundamental mode. It is found that increased absorption in the cladding layer results in increased lateral extent of the guided mode. At a critical absorption strength, the guided mode becomes unconfined in the lateral direction. This transition can be rationalized in part in terms of the effective index method, which provides a simple approximate way to calculate the characteristics of waveguides with two-dimensional index profiles

Keywords

claddings; eigenvalues and eigenfunctions; electro-optical devices; electroabsorption; optical losses; optical waveguide theory; semiconductor quantum wells; Galerkin´s method; Helmholtz equation; attenuation; cladding layer; critical absorption strength; effective index method; eigenmodes; exact mode propagation constants; fundamental mode; guided mode; guiding region; lateral confinement; lateral extent; lossy field-induced optical waveguides; multiquantum well cladding region; propagation direction; slab waveguides; spatially selective electric field; two-dimensional index profiles; Absorption; Attenuation; Equations; Moment methods; Optical attenuators; Optical computing; Optical losses; Optical waveguides; Propagation constant; Slabs;

fLanguage

English

Journal_Title

Lightwave Technology, Journal of

Publisher

ieee

ISSN

0733-8724

Type

jour

DOI

10.1109/50.296193

Filename

296193