Generation of ultrashort pulses with minimum duration of 90 fs in a hybrid mode-locked erbium-doped all-fibre ring laser

Regimes of ultrashort pulse generation in an erbiumdoped all-fibre ring laser with hybrid mode locking based on singlewall carbon – boron nitride nanotubes and the nonlinear Kerr effect in fibre waveguides are studied. Stable dechirped ultrashort pulses are obtained with a duration of ~90 fs, a repetition rate of ~42.2 MHz, and an average output power of ~16.7 mW, which corresponds to a pulse energy of ~0.4 nJ and a peak laser power of ~4.4 kW.