A numerical model is presented to predict the time-resolved evolution of the spatial intensity distribution of the laser pulses in the super-Gaussian mirror resonator, taking into account diffraction and stored energy depletion. The beam-quality factor M2 is calculated during the pulse evolution. Simulation results show that gain saturation affects the beam quality of the Q-switched solid-state lasers, the corresponding values of the M2 parameter increase during the pulse evolution. The spatial distribution of laser pulse first starts on the resonator axis with a Gaussian-shaped spot, then expands very quickly and forms a donut-shaped profile towards the end of the pulse.
© 2007 Chinese Optics Letters
(140.0140) Lasers and laser optics : Lasers and laser optics
(140.3540) Lasers and laser optics : Lasers, Q-switched
(140.3580) Lasers and laser optics : Lasers, solid-state
(140.4480) Lasers and laser optics : Optical amplifiers
(140.4780) Lasers and laser optics : Optical resonators
Dingxiang Cao, Xiaofeng Wang, Shaobo He, Haiwu Yu, and Wangguo Zheng, "Analysing the pulse formation of Q-switched Nd:YAG laser with super-Gaussian mirror resonator," Chin. Opt. Lett. 5, S44-S45 (2007)