An end-pumped Nd:YAG planar waveguide laser with an optical to optical conversion efficiency of 58%

A thermal-bonded Nd:YAG planar waveguide laser with an O-O conversion efficiency of 58% was demonstrated for the first time to our knowledge. The waveguide was end-pumped by a fiber-coupled laser diode operating at 808 nm. A maximum output power of 2.90 W at 1064 nm was achieved with an M2 value of 2.6 in the guided direction for a pump power of 5.0 W. The results indicate that the planar waveguide laser can reach high O-O conversion efficiency and has a promising prospect for efficient and high optical quality laser sources.