High efficiency Nd:YAG ceramic eye-safe laser operating at 1442.8 nm.

We report on a diode-pumped Nd:YAG ceramic laser operating at 1442.8 nm for the first time. In our experiment, two different Nd:YAG ceramics with the Nd-doped concentrations of 1.0 and 0.6 at. % and a Nd:YAG with the Nd-doped concentration of 1.0 at. % were used as the laser gain mediums, respectively. At a pump power of 20.7 W, a maximum output power of up to 3.96 W with optical-to-optical efficiency of up to 19.1% was obtained by using the 1.0 at. % Nd-doped ceramic as the laser gain medium. To the best of our knowledge, this is the highest output power of a LD-pumped 1.44 μm Nd:YAG ceramic laser and the highest optical-to-optical efficiency of a LD-pumped 1.44 μm Nd-doped crystal laser.