▎ 摘 要
Ultrafast lasers with tunable capabilities of pulse duration and spectrum have widespread applications in telecommunication, spectroscopy, and nonlinear optical bio-imaging. However, traditional mechanical and electrical tuning methods are still challenging for precise and stable controlling. Based on graphene's photo-thermal effect, we tune the bandwidths and wavelengths of chirped fiber Bragg gratings with flexible graphene-coating approaches. By inserting the fabricated devices into an ultrafast fiber laser cavity, durations and wavelengths of the generated pulses can be all-optically tuned with sensitivities of 470 fs/mW and 2.9 pm/mW, separately. Such an optical-controlled method provides a compact and precise way to regulate various laser properties. (C) 2018 Optical Society of America.