Spectral properties of strongly coupled 1.5 µm DFB laser diodes

Author

Westbrook, Leslie D. ; Henning, I.D. ; Nelson, Andrew W. ; Fiddyment, Philip J.

Author_Institution

British Telecom Res. Labs., Martlesham Heath, Ipwich, England

Volume

21

Issue

6

fYear

1985

fDate

6/1/1985 12:00:00 AM

Firstpage

512

Lastpage

518

Abstract

Spectral measurements of strongly coupled DFB lasers operating at 1.5 μm are presented. The magnitude of the coupling coefficient $k$ in these devices was determined to be 80 cm^-1for lasers with $\\lambda = 1.12 \\mu$ m cladding layers and 160 cm^-1for devices with $\\lambda = 1.3 \\mu$ m cladding layers. These values for $k$ are believed to be the largest reported for 1.5 μm DFB lasers. CW spectral linewidths as low as 10 MHz at 15 mW output power were obtained, and the linewidth was observed to vary approximately as the inverse of the device length cubed. Spectral measurements performed under 2 Gbit/s direct modulation exhibited a side mode suppression ratio of >38 dB. The effects of transient wavelength chirping were also investigated in detail and the maximum wavelength deviation was found to be ≃1.5 Å.

Keywords

Distributed feedback (DFB) lasers; Gallium materials/lasers; Diode lasers; Distributed feedback devices; Epitaxial growth; Etching; Gratings; Laser feedback; Laser modes; Optical coupling; Semiconductor lasers; Waveguide lasers;

fLanguage

English

Journal_Title

Quantum Electronics, IEEE Journal of

Publisher

ieee

ISSN

0018-9197

Type

jour

DOI

10.1109/JQE.1985.1072694

Filename

1072694