Measurement of linewidth enhancement factor of semiconductor lasers by modified direct frequency-modulation method

Author

Kikuchi, Kazuro ; Iwasawa, Hiroshi

Author_Institution

Dept. of Electron. Eng., Tokyo Univ.

Volume

24

Issue

13

fYear

1988

fDate

6/23/1988 12:00:00 AM

Firstpage

821

Lastpage

822

Abstract

The frequency modulation characteristics of 1.3 μm DFB lasers below the relaxation resonance reveal two different types of response: the in-phase response between the frequency modulation (FM) and the amplitude modulation (AM), and the out-of-phase response between them. In both cases, the ratio of the FM index to the AM index is strongly dependent on the modulation frequency; however, when the modulation frequency is increased beyond the relaxation resonance, this value approaches the linewidth enhancement factor. On the basis of this result, the linewidth enhancement factors of 1.3 μm DFB lasers with different amounts of wave-length detuning are determined

Keywords

distributed feedback lasers; frequency modulation; laser transitions; laser variables measurement; optical modulation; semiconductor junction lasers; spectral line breadth; 1.3 micron; AM index; DFB lasers; FM index; amplitude modulation; frequency-modulation; in-phase response; linewidth enhancement factor; modified direct FM method; modulation characteristics; out-of-phase response; relaxation resonance; semiconductor lasers; wave-length detuning;

fLanguage

English

Journal_Title

Electronics Letters

Publisher

iet

ISSN

0013-5194

Type

jour

Filename

8356