We report numerical results for gain saturation in circular-grating distributed-feedback semiconductor lasers. Our model includes a radially varying nonlinear gain and a uniformly distributed grating loss in the solution of the coupled-mode equations. Our results show that lossy, high-power operation results in an optimum coupling strength for efficient conversion of pump power into useful output power. Our results also show a multimode spectrum for large-coupling strengths, a consequence of mode competition induced by a spatially varying gain distribution. Single-mode selection entails operating at approximately the optimum coupling coefficient determined for efficient pumping.
|Original language||English (US)|
|Number of pages||6|
|Journal||Journal of the Optical Society of America B: Optical Physics|
|State||Published - Aug 1997|
ASJC Scopus subject areas
- Statistical and Nonlinear Physics
- Atomic and Molecular Physics, and Optics