All-solid-state 589-nm pulse generation using sum frequency of Stokes Raman lasers

We report a 589-nm laser using the sum-frequency generation (SFG) of 1.158- and 1.197-μm Stokes Raman lasers. These Stokes lasers are based on two KGd(WO4)2 and Ba(NO3)2 external Raman laser oscillators. First, a high-energy 1064-nm source was built to pump stimulated Raman scattering. Multiorder Stokes lasers with pulse energies of 402 and 220 mJ were generated from Raman laser oscillators with 2.26-J pumping. Furthermore, these two Stokes beams were simultaneously delivered into a potassium dihydrogen phosphate crystal for SFG. Finally, a 31.7-mJ laser at 589 nm was achieved with pulse duration of 6.9 ns and repetition rate of 1 Hz. These experimental results provide practical alternative to generate high-energy short-pulse 589-nm laser beams for related applications.