High-power continuous-wave Nd lasers under dioide pumping directly into the 4F3/2 emitting level

Output performances of Nd-based lasers that were pumped with diode lasers directly into the 4F3/2 emitting level has been investigated at various wavelengths of emission. The end-pumping scheme was used to demonstrate efficient laser emission in the watt-range at 0.94 µm, 1.06 µm and 1.34 µm in Nd:YAG pumped at 885 nm. Nd:YVO4 and Nd:GdVO4 thin-disk lasers with high power emission at 1.06 µm were realized under multi-pass pumping at 880 nm, and for the first time laser emission at 0.91 µm was achieved in this configuration. Intracavity frequency-doubled lasers with emission in the green and blue spectral ranges were obtained. Thus, an end-pumped Nd:GdVO4 laser with 5 W output power at 0.53 µm, and Nd:YVO4 and Nd:GdVO4 thin-disk lasers with output power in excess of 4 W at 0.53 µm were realized. Nd-vanadates thin-disk lasers with ~1 W power into 0.45 µm 'deep-blue' visible spectra were demonstrated. Comparative results with the traditional pumping at 0.81 µm into the highly absorbing 4F5/2 level are presented, proving the advantage of the direct 4F3/2 pumping.