Improved compression of INGAASP gain-switched DFB laser pulses using polarization dispersion effects

Gain-switched semiconductor lasers are versatile sources for short pulse generation that offer the advantage of broad repetition rate tunability, ease of use, compactness and stability. They however suffer from a large chirp that can be detrimental in many applications. We both analytically and experimentally demonstrate here a method to generate nearly transform limited pulses from a gain-switched laser using index and polarization dispersion within a set of fibers. The effect of the polarization dispersion is also investigated after a soliton compression stage leading to subpicosecond pulses.