Abstract
The external cavity lasers using fiber gratings are expected to be useful as the light source in WDM systems, because of their high selectivity of lasing wavelength. But it is pointed out that these lasers are unstable by the mode hopping when the temperature is changing. In this paper, we simulated the mode hopping characteristics of these lasers, by the combination of the resonance analysis considering the reflection profile of fiber gratings and rate equations. Good agreement between calculated and experimental results were obtained, so the applicability of the simulation methods were confirmed. Moreover we revealed the relationship between the structure of the lasers and the temperature dependence of the lasing character, considering thermal shift of wavelength and gain difference between main mode and side mode.
