High repetition rate actively mode-locked Er:fiber laser with tunable pulse duration

摘要

An actively mode-locked fiber laser with controllable pulse repetition rate and tunable pulse duration is presented,in which an optical delay line(ODL)is used to adjust the cavity length precisely for regulating the repetition rate,and a semiconductor optical amplifier(SOA)is introduced for enabling the pulse duration control.Experimentally,continuous tuning of the repetition rate from 2 GHz to 6 GHz is realized,which is limited by the availability of an even higher repetition rate radiofrequency(RF)source.Specifically,when the repetition rate is fixed at 2.5 GHz,the pulse duration can be tuned from 4 ps to30 ps,which is,to the best of our knowledge,the widest tuning range of pulse duration ever achieved in a gigahertz(GHz)repetition rate actively mode-locked 1.5μm fiber laser oscillator.