Graphene oxide mode-locked Yb:GAGG bulk laser operating in the femtosecond regime

• High-quality graphene oxide saturable absorber was successfully fabricated with 1–2 layer graphene oxide.
• Femtosecond pulse generation from a graphene oxide mode locked bulk laser was demonstrated for the first time.
• The results present here indicate that GO is a promising saturate absorber material for femtosecond bulk laser.

High-quality graphene oxide saturable absorber (SA) is successfully fabricated with 1–2 layer graphene oxide. By employing this SA, we have demonstrated femtosecond pulse generation from a graphene oxide passively mode locked bulk laser for the first time to our best knowledge. With two Gires–Tournois interferometer mirrors for dispersion compensation, pulses as short as 493 fs with an average power of 500 mW are obtained at the central wavelength of 1035.5 nm. These results presented here indicate the great potential of GO for generating femtosecond mode-locked pulses in the bulk laser.