Frequency-resolved optical gating for characterization of single- and dual-wavelength pulse generation from a self-seeded gain-switched Fabry-Perot laser

Multiwavelength picosecond pulse sources are important for the future development of high-capacity wavelength- and time-division multiplexed optical systems. A simple technique to generate picosecond pulses at selected wavelengths involves the self-seeding of gain-switched Fabry-Perot (FP) laser diodes. With this technique, an external cavity is used to reinject light back into the gain-switched laser at one or more longitudinal-mode frequencies in order to obtain single or multiwavelength operation. The use of the resulting multiwavelength pulses in high-speed optical communication systems will be highly dependent on their exact intensity and phase characteristics. In this paper we use the measurement technique of frequency-resolved optical gating (FROG) to completely characterize the intensity and phase of picosecond pulses from a self-seeded gain-switched FP laser operating as a single- and a dual-wavelength source.