Long-term wavelength drift of the order of -0.01 nm/yr for 15 free-running DFB laser modules

Abstract

Wavelength-division-multiplexing (WDM) technologies are of interest for significantly increasing the transport capacity1 and lowering the cost2 of optical-fiber networks. One potential application of WDM technology would be in the interoffice networks of the local-exchange telephone carriers. Stable wavelength operation of the transmitter lasers is essential in WDM networks. To simplify network operations and reduce equipment costs, it is desirable to use a simple wavelength-stabilization technique that relies only on constant laser-diode temperature and current control,2 without the use of active wavelength stabilization derived from an optical spectrometer.