Femtosecond soliton generation in a praseodymium fluoride fiber laser

We report what is to our knowledge the first femtosecond pulse generation at 1.3 micro m in a Pr 3(+)-doped fluoride fiber laser. After optimization of the cavity length and dispersion, the laser generated pulses as short as 620 fs. We also describe self-stabilization and self-organization of the output pulse train at repetition rates from the fundamental cavity frequency of 700 kHz up to 440 MHz and report on polarization effects.