Supermodes of grating-coupled multimode waveguides and application to mode conversion between copropagating modes mediated by backward Bragg scattering

Author

Peral, Eva ; Yariv, Amnon

Author_Institution

Dept. of Appl. Phys., California Inst. of Technol., Pasadena, CA, USA

Volume

17

Issue

5

fYear

1999

fDate

5/1/1999 12:00:00 AM

Firstpage

942

Lastpage

947

Abstract

An analysis of multimode waveguides where several modes are coupled via quasiperiodic perturbations is presented. The supermodes (or eigenmodes) of the structure are derived and orthonormality considerations are discussed. In addition, a new type of mode converter between copropagating modes is proposed, where mode conversion is mediated by a backward propagating mode. Adiabatic and nonadiabatic coupling coefficients are considered and the supermode formalism is used to conveniently describe the mode of operation of the device

Keywords

Bragg gratings; diffraction gratings; eigenvalues and eigenfunctions; light scattering; optical waveguide theory; optical waveguides; perturbation theory; adiabatic coupling coefficients; backward Bragg scattering; backward propagating mode; copropagating modes; eigenmodes; grating-coupled multimode waveguide supermodes; mode conversion; multimode waveguides; nonadiabatic coupling coefficient; orthonormality considerations; quasiperiodic perturbations; supermode formalism; Bragg gratings; Coupled mode analysis; Distributed feedback devices; Equations; Fiber gratings; Optical fiber theory; Optical refraction; Optical scattering; Optical waveguide theory; Optical waveguides;

fLanguage

English

Journal_Title

Lightwave Technology, Journal of

Publisher

ieee

ISSN

0733-8724

Type

jour

DOI

10.1109/50.762915

Filename

762915