1.5 GHz Pulse Generation From a Monolithic Waveguide Laser With a   Graphene-Film Saturable Output Coupler
  We fabricate a saturable absorber mirror by coating a graphene film on an output coupler mirror. This is then used to obtain Q-switched mode-locking from a diode pumped linear cavity waveguide laser inscribed in Ytterbium-doped Bismuthate Glass, with high slope and optical conversion efficiencies. The laser produces mode-locked pulses at 1039nm, with 1.5GHz repetition rate at an average 202mW output power. This performance is due to the combination of the graphene saturable absorber with the high quality laser glass. 
R. Mary, S. J. Beecher, G. Brown, F. Torrisi, S. Milana, D.Popa, T.   Hasan, Z. Sun, E. Lidorikis, S. Ohara, A. C. Ferrari, ...
cond-mat.mes-hall cond-mat.mtrl-sci physics.optics