Modeling and optimization of the YAG:Yb microchip laser passively Q-switched by YAG:Cr absorber

Based on analytical and numerical solutions of the rate equations system and the heat conductivity equation, the model of the quasi-three-level passively Q-switched YAG:Yb/YAG:Cr microchip laser is developed. The obtained results are used for its optimization, i.e., for the determination of the output mirror reflectivity, the pumping beam radius, the thickness of the absorber and the phototropic centers concentration maximizing the energy in the laser pulse. The influence of the thermal load on the spatial parameters of the laser beam is also determined.