70-Femtosecond Gaussian pulse generation in a dispersion-managed erbium-doped fibre laser

We experimentally demonstrated the generation of transform-limit Gaussian ultrashort pulses as short as 70 fs from a dispersion-managed mode-locked erbium-doped fibre (EDF) laser. The output spectrum is close to the Gaussian profile with a full-width half-maximum (FWHM) output of 49 nm, and the measured autocorrelation trace exhibits the Gaussian profile. The shortest pulse duration of 70 fs was observed after external recompression. The time-band product is 0.44, showing the best transform limit pulse.