▎ 摘　　要

We introduce a saturable absorber by coating double graphene films on a fusion stretched microfiber waveguide, compare with employing graphene films sandwiched between fiber ferrules that stable Q-switched pulse disappeared at 240 mW pump, it shows feasibility for improved Q-switching operation at higher optical damage threshold ( up to 600 mW), repetition rate increased from 50.38 to 73.06 kHz and pulse energy from 76.82 to 93.76 nJ, as pump power change from 300 to 500 mW. And our laser produced 1.94 ps mode-locked pulse at similar to 1560 nm by GMF. Bilayer chemical vapor deposition synthesized graphene was used to enhance the evanescent interaction with the microfiber.