An anomalous modulation in the wavelength spectrum has been observed in lasers with spotsize converters. This intensity modulation is shown to be caused by beating between the fundamental lasing mode and radiation modes in the taper. This results in a periodic modulation in the net gain spectrum, which causes wavelength jumps between adjacent net gain maxima, and a drive current dependent spectral width that is expected to affect system performance. The amplitude of this spectral modulation is reduced significantly by either using an angled rear-facet which reflects the beating radiation modes away from the laser axis, or by using a nonlinear, adiabatic taper.
|Number of pages||15|
|Journal||Optical and Quantum Electronics|
|Publication status||Published - 1 Oct 2002|
- Coupled mode analysis
- Laser stability
- Semiconductor lasers
- Spectral analysis