Complex-coupled DFB lasers: advantages and drawbacks of gain and radiation loss grating

Author

Gourgon, C. ; Robadey, J. ; Martin, D. ; Filipowitz, F. ; Mahler, L. ; Ky, N.H. ; Deveaud, D. ; Reinhart, F.K.

Author_Institution

Lab. des Technols. de la Microelectronique, CNRS, Grenoble, France

Volume

12

Issue

7

fYear

2000

fDate

7/1/2000 12:00:00 AM

Firstpage

765

Lastpage

767

Abstract

Two types of InGaAs-GaAs-AlGaAs complex-coupled distributed feedback laser structures grown by molecular beam epitaxy are compared. The first structure uses interrupted quantum wells (QW´s) grown over a grating. Its properties strongly depend on the interface cleaning resulting in nonreproducible threshold current densities. The second structure includes three uniform QW´s, the gain coupling being induced by the vertical radiation of the second order grating. This last structure has reproducible, low continuous wave threshold current densities (jth=300 A/cm/sup 2/). The coupling strength and its origin are described for the two structures. Both structures have high mono-mode yield (>75%) and side-mode suppression ratios larger than 40 dB.

Keywords

III-V semiconductors; aluminium compounds; current density; diffraction gratings; distributed feedback lasers; gallium arsenide; indium compounds; laser beams; laser feedback; laser modes; molecular beam epitaxial growth; optical fabrication; optical losses; quantum well lasers; InGaAs-GaAs-AlGaAs; complex-coupled DFB lasers; complex-coupled distributed feedback laser structures; continuous wave threshold current densities; coupling strength; gain; gain coupling; grating; interface cleaning; interrupted quantum wells; molecular beam epitaxy; mono-mode yield; nonreproducible threshold current densities; radiation loss grating; second order grating; side-mode suppression ratios; uniform quantum wells; vertical radiation; Cleaning; Distributed feedback devices; Etching; Gratings; Laser feedback; Laser theory; Molecular beam epitaxial growth; Optical coupling; Quantum well lasers; Threshold current;

fLanguage

English

Journal_Title

Photonics Technology Letters, IEEE

Publisher

ieee

ISSN

1041-1135

Type

jour

DOI

10.1109/68.853493

Filename

853493