Waveguide-saturable absorber fabricated by femtosecond pulses in YAG:Cr(4+) crystal for Q-switched operation of Yb-fiber laser.

A waveguide-saturable absorber with low propagation loss is fabricated by femtosecond pulses in YAG:Cr(4+) crystal. Q-switch operation of a Yb fiber laser with the new saturable absorber having absorption saturation parameters similar to the bulk YAG:Cr(4+) crystal is demonstrated.