High-power actively Q-switched Nd:GdVO4 laser end-pumped by a fiber-coupled diode-laser array

Abstract An end-pumped acousto-optically Q-switched Nd:GdVO 4 laser has been demonstrated, from which 7.25 W average output power at 1.06 μm at pulse repetition frequency (PRF) of 60 kHz was obtained with an optical conversion efficiency of 38.1% and an averaged slope efficiency of 43.5%. At incident pump power of 17 W, the highest single pulse energy and peak power were achieved when the laser was operated at a PRF of 10 kHz, and were determined to be 340 μJ and 26.2 kW, respectively. The shortest laser pulse with FWHM width of 11 ns was observed at PRF of 20 kHz. Through intracavity frequency doubling, we obtained 2.18 W average green output power with pulse width of 45 ns at a PRF of 25 kHz, the corresponding optical conversion efficiency was 21.8%, and the resulting single pulse energy and peak power were determined to be 87.2 μJ and 1.94 kW, respectively. The results of theoretical calculations on the basis of rate equations are also presented, showing close consistency with the experimental data.