<title>Theory And Experiment On Distributed Feedback Lasers With Chirped Grating</title>

Abstract

It is shown that small and gradual variations in the effective refractive-index or the grating period as little as 10-4 along the laser axis can have significant effects on the lasing characteristics of DFB (distributed feedback) lasers. Through numerical analyses based on the coupled-mode equations, it has been predicted that, in comparison with a DFB laser with uniform axial distribution of the effective refractive-index or the grating period, the axial-mode selectivity and the threshold gain of the lowest mode are much improved in a DFB laser with symmetric cosineor quadratic distribution and are much deteriorated in that with asymmetric linear distribution. Optically pumped GaAs DFB lasers with variable grating period have been fabricated by a new holographic interference technique, and experimental results consistent with the theoretical predictions are obtained.© (1981) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.