All-Polarization-Maintaining Femtosecond Fiber Lasers Using Graphene Oxide Saturable Absorber

We demonstrate the mode-locking operation in an all-polarization-maintaining (all-PM) erbium-doped fiber laser by exploiting graphene oxide saturable absorber for the first time. The self-started, environmentally stable laser directly generates linearly polarized soliton pulses of 502 fs duration at a repetition rate of 48.2 MHz with an extinction ratio of 21.3 dB. The optical spectrum centered at 1555.92 nm has 3-dB bandwidth of 6 nm. This unique combination of the all-PM configuration and the novel graphene oxide saturable absorber offers an ideal approach to fabricate a compact single-polarization femtosecond source with high environmental stability.