Time-resolved chirp measurements and laser-threshold measurements are used to understand the chirp performance of integrated laser electroabsorption modulators. The different effects of the intrinsic modulator chirp component and chirp caused by optical feedback, from reflection at the output facet into the laser, are observed. A figure of merit is introduced to assess the chirp performance, which shows good correlation with dispersion penalty measurements. The effect of reflection-induced chirp is considerably reduced by operating the modulator with negative chirp. An optimized device is reported, which delivers purely negative chirp with reasonable optical power.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Electrical and Electronic Engineering