Diode-pumped doubly Q-switched c-cut Nd:GdVO4 laser with AO modulator and GaAs saturable absorber

Using both acoustic- optic (AO) modulator and GaAs saturable absorber in the same cavity, a diode-pumped doubly Q-switched c-cut Nd:GdVO4 laser has been realized. This laser can generate the more symmetric pulse with shorter pulse width in comparison with singly AO or GaAs Q- switched laser. We also made a comparison between c-cut and a-cut Nd: GdVO4 crystals and the experimental results shows that the doubly Q-switched c- cut Nd: GdVO4 laser can generate narrower pulse with higher peak power when the incident pump power higher than 3.4 W. The coupled rate equations, in which the spatial distributions of the intracavity photon density and the population- inversion density are taken into account, are introduced to theoretically analyze the experimental results, and the experimental results are in fair agreement with the numerical solutions.