Abstract
Low threshold and compact cw Nd:YVO4 self-Raman lasers at 1176 nm and sum-frequency mixing of fundamental and first-Stokes wavelengths are demonstrated. A 20-mm Nd:YVO4 crystal is adopted in a compact plane-concave resonator. The results show that the cw Raman conversion is sensitive to cavity length. At an incident pump power of 22.5 W, output power of 1.53 W at 1175.6 nm is achieved, corresponding to the threshold of only 0.8 W and the slop efficiency of 8.1%. Intra-cavity sum-frequency generation is realized in a type-II phase-matching cut KTP crystal, 480 mW at 558.6 nm is obtained at incident pump power of 12 W.