Diode-pumped passively Q-switched 912 nm Nd:GdVO4 laser and pulsed deep-blue laser by intracavity frequency-doubling

diode-end-pumped passively Q-switched 912 nm Nd:GdVO4/Cr4+:YAG laser and its efficient intracavity frequency-doubling to 456 nm deep-blue laser were demonstrated in this paper. Using a simple V-type laser cavity, pulsed 912 nm laser characteristics were investigated with two kinds of Cr4+:YAG crystal as the saturable absorbers, which have the different initial transmissivity (T-U) of 95% and 90% at 912 nm. When the T-U = 95% Cr4+:YAG was used, as much as an average output power of 2.8 W 912 nm laser was achieved at an absorbed pump power of 34.0 W. and the pulse width and the repetition rate were similar to 40.5 ns and similar to 76.6 kHz, respectively. To the best of our knowledge, this is the highest average output power of diode-pumped passively Q-switched Nd3+ -doped quasi-three-level laser. Employing a BiBO as the frequency-doubling crystal, 456 nm pulsed deep-blue laser was obtained with a maximum average output power of 1.2 W at a repetition rate similar to 42.7 kHz. (c) 2010 Elsevier B.V. All rights reserved.