The intracavity photon density and the initial population-inversion density in the diode-pumped passively <i>Q</i>-switched laser rate equations are assumed to be Gaussian spatial distributions. These space-dependent rate equations are solved numerically, and a group of general curves are generated. These curves clearly show the dependence of the pulse characteristics on the pump- to laser-mode size ratio and the parameters of the gain medium, the saturable absorber, and the resonator. They can also be used to estimate the pulse parameters of an arbitrary diode-pumped passively <i>Q</i>-switched laser and to determine the optimal pump- to laser-mode size ratio. In addition, these curves are not limited to diode-pumped lasers. Sample calculations for a diode-pumped Nd<sup>3+</sup>:YVO<sub>4</sub> laser and a flash-lamp pumped Nd<sup>3+</sup>:YAG laser are presented to demonstrate the use of the curves and the related formulas.
© 2000 Optical Society of America
(140.3430) Lasers and laser optics : Laser theory
(140.3460) Lasers and laser optics : Lasers
(140.3480) Lasers and laser optics : Lasers, diode-pumped
(140.3540) Lasers and laser optics : Lasers, Q-switched
(140.3580) Lasers and laser optics : Lasers, solid-state
Xingyu Zhang, Shengzhi Zhao, Qingpu Wang, B. Ozygus, and H. Weber, "Modeling of passively Q-switched lasers," J. Opt. Soc. Am. B 17, 1166-1175 (2000)