Highly efficient 1-μm continuous-wave laser emission in 3-mm-thick, 0.5- and 1.0-at. % Nd:GdVO<sub>4</sub> crystals longitudinally pumped at 879 nm into the laser emitting level is reported. Under Ti:sapphire pumping, the slope efficiency in absorbed power is ~80% for both crystals, while the slope efficiency, the optical-to-optical efficiency (at 1700-mW pump power), and the laser threshold in incident power are 79%, 78%, and 31 mW for 0.5-at. % Nd and 80%, 77%, and 40 mW for 1.0-at. % Nd, respectively. The slope efficiency is close to the quantum defect limit, the difference being fully accounted for by the residual optical losses. Under 879-nm diode laser pumping, the slope efficiency and the optical-to-optical efficiency in absorbed power of the 0.5-at. % Nd:GdVO<sub>4</sub> crystal are 60% and 53%, owing to poorer superposition of the pumped and the laser mode volumes.
© 2003 Optical Society of America
(140.3380) Lasers and laser optics : Laser materials
(140.3530) Lasers and laser optics : Lasers, neodymium
(160.5690) Materials : Rare-earth-doped materials
(300.6280) Spectroscopy : Spectroscopy, fluorescence and luminescence
V. Lupei, N. Pavel, Y. Sato, and T. Taira, "Highly efficient 1063-nm continuous-wave laser emission in Nd:GdVO4," Opt. Lett. 28, 2366-2368 (2003)