All-fiber integrated 10 GHz repetition rate femtosecond laser source based on Raman compression of pulses generated through spectral masking of a phase-modulated diode.

We report the development of a 10 GHz repetition rate all-fiber integrated femtosecond source tunable around 1.55 μm. A phase modulator and sharp spectral filter are used to convert the output of a tunable CW diode to a 10 GHz pulse train. These pulses are compressed using Raman soliton adiabatic compression in a 21 km long length of fiber to generate sub-300-fs duration pulses at a 10 GHz repetition rate. By tuning the wavelength of the diode and appropriate filtering, similar performance was achieved over a 20 nm bandwidth.