High-power diode-pumped Nd:GdVO₄/KGW Raman laser at 578  nm

A diode-pumped neodymium-doped gadolinium vanadate (Nd:GdVO₄) laser is developed as a compact efficient yellow light at 578 nm by means of intracavity stimulated Raman scattering (SRS) in a potassium gadolinium tungstate (KGW) crystal and the second-harmonic generation in a lithium triborate crystal. The SRS process with a shift of 768cm^-1 is achieved by setting the polarization of the fundamental wave along the N_g axis of the KGW crystal. The self-Raman effect arising from the Nd:GdVO₄ crystal is systematically explored by employing two kinds of coating specification for the output coupler. With a specific coating on the output coupler to suppress the self-Raman effect, the maximum output power at 578 nm can reach 3.1 W at a pump power of 32 W. Moreover, two different lengths for the Nd:GdVO₄ crystal are individually used to verify the influence of the self-Raman effect on the lasing efficiency.