Title :
Dynamic coherence measurements of index- and gain-guided VCSELs
Author :
Kemme, S.A. ; Kostuk, R.K. ; Chun, C.K.Y.
Author_Institution :
Opt. Sci. Center, Arizona Univ., Tucson, AZ, USA
fDate :
5/1/1997 12:00:00 AM
Abstract :
Coherence properties of several different types of VCSELs are examined with constant and modulated injection current with a bandwidth typical of that used in telecommunications. Large signal modulation of index-guided single transverse-mode VCSELs is found to reduce the coherence length by more than a factor of ten relative to the direct current configuration. Multiple transverse-mode index-guided VCSELs have similar coherence lengths when operated dc and modulated, and shorter than that of the single transverse-mode VCSELs. Gain-guided multiple transverse-mode VCSELs also have shorter coherence lengths than single transverse-mode VCSELs and under modulation can have coherence lengths as low as 0.5 cm.
Keywords :
coherence length; electro-optical modulation; laser cavity resonators; laser modes; laser noise; light coherence; optical transmitters; quantum well lasers; refractive index; semiconductor device noise; surface emitting lasers; bandwidth; coherence length; coherence lengths; direct current configuration; dynamic coherence measurements; gain-guided VCSELs; gain-guided multiple transverse-mode VCSELs; index-guided VCSELs; index-guided single transverse-mode VCSELs; large signal modulation; modulated injection current; multiple transverse-mode index-guided VCSELs; shorter coherence lengths; similar coherence lengths; single transverse-mode VCSELs; telecommunications; Coherence; Gain measurement; Optical interconnections; Optical modulation; Optical noise; Optical sensors; Semiconductor device noise; Stimulated emission; Surface emitting lasers; Vertical cavity surface emitting lasers;
Journal_Title :
Photonics Technology Letters, IEEE
