Efficient continuous-wave intracavity frequency-doubled Nd:YAG-LBO blue laser at 473 nm under diode pumping directly into the emitting level

Abstract

We report the efficient blue laser at 473 nm generation by intracavity frequency doubling of a continuous wave laser operation of a 885 nm diode direct pumped Nd:YAG laser on the 4F3/2 → 4I9/2 transition at 946 nm. A LiB3O5 (LBO) crystal, cut for critical type I phase matching at room temperature is used for second harmonic generation of the laser. At the absorbed pump power of 18.7 W, as high as 4.3 W of continuous wave output power at 473 nm is achieved with 15 mm long LBO. The optical-to-optical conversion efficiency with respect to the absorbed power is up to 0.23, and the beam quality M2 value is 1.2.