▎ 摘　　要

A mode-locked Erbium-doped fibre laser with graphene as a saturable absorber is numerically simulated. Mode-locked operation and controllable pulse compression through dispersion management by using dispersion-decreasing fibres (DDF) in a cavity ring are investigated. By examining several dispersion profiles for DDF, it is found that for a fixed DDF length maximum compression factor is achieved by using a hyperbolic dispersion profile. Higher compression factor is attributed to dispersion decreasing along DDF. In addition, it is shown that graphene mode-locked operation along with dispersion management results in the generation of pulses that are shorter than what has been already achieved by similar cavity parameters. Furthermore, output pulse duration and repetition rate can be tuned by using DDFs with different dispersion profiles and lengths.