Pulse LDA-pumped passively Q-switched mode locked Nd:YVO4 laser with a GaAs saturable absorber

A passively Q-switched pulse-LDA(laser-diode-array)-pumped Nd:YVO4 laser using As + ion-implanted GaAs as a saturable absorber is demonstrated. In the Q-switching experiment, the laser produces one Q-switching pulse in every pumping pulse duration and a Q-switching pulse width 7 ns is achieved. When the pumping power is increased a Q-switched mode-locked laser is achieved. Using a 60% initial transmission GaAs wafer, the modulation depth of larger than 95% is obtained. The repetition rate of the mode-locked pulses in the Q-switched envelope is 991MHz. The effects of the pumping pulse energy, pumping pulse width and repetition rate on the characteristics of the Q-switched mode-locked pulses are also investigated respectively. The experimental results are discussed as well in the paper.