An out-of-plane grating coupler for efficient butt-coupling between compact planar waveguides and single-mode fibers

Author

Taillaert, Dirk ; Bogaerts, Wim ; Bienstman, Peter ; Krauss, Thomas F. ; Van Daele, Peter ; Moerman, Ingrid ; Verstuyft, Steven ; De Mesel, Kurt ; Baets, Roel

Author_Institution

Dept. of Inf. Technol., Ghent Univ., Belgium

Volume

38

Issue

7

fYear

2002

fDate

7/1/2002 12:00:00 AM

Firstpage

949

Lastpage

955

Abstract

We have designed and fabricated an out-of-plane coupler for butt-coupling from fiber to compact planar waveguides. The coupler is based on a short second-order grating or photonic crystal, etched in a waveguide with a low-index oxide cladding. The coupler is optimized using mode expansion-based simulations. Simulations using a 2-D model show that up to 74% coupling efficiency between single-mode fiber and a 240-nm-thick GaAs-AlO_x waveguide is possible. We have measured 19% coupling efficiency on test structures

Keywords

diffraction gratings; integrated optics; optical couplers; optical fibre couplers; optical planar waveguides; photonic band gap; 19 percent; 2-D model; 240 nm; GaAs-AlGaAs; GaAs-AlO; GaAs-AlO_x waveguide; butt-coupling; compact planar waveguides; coupler optimization; coupling efficiency; large-scale photonic integrated circuits; low-index oxide cladding; mode expansion-based simulations; out-of-plane grating coupler; photonic crystal; short second-order grating; single-mode fibers; test structures; Circuit simulation; Coupling circuits; Electromagnetic waveguides; Fiber gratings; Optical coupling; Optical fiber couplers; Optical planar waveguides; Optical waveguides; Photonic crystals; Planar waveguides;

fLanguage

English

Journal_Title

Quantum Electronics, IEEE Journal of

Publisher

ieee

ISSN

0018-9197

Type

jour

DOI

10.1109/JQE.2002.1017613

Filename

1017613