Highly efficient laser action in femtosecond-written Nd:yttrium aluminum garnet ceramic waveguides

We report continuous wave 1.06 mu m laser operation in an optical waveguide fabricated in a Nd:YAG ceramic by femtosecond laser writing. Single mode and stable laser oscillation have been achieved by using the natural Fresnel reflection for optical feedback. Output laser power in excess of 80 mW and a laser slope efficiency of 60% have been demonstrated. (C) 2008 American Institute of Physics.