Modeling of continuous-wave self-frequency-doubling microchip laser for Yb/sup 3+/:YAl/sub 3/(BO/sub 3/)/sub 4/ crystal

Based on a quasi-three-level system, a model of continuous wave (CW) self-frequency-doubling (SFD) laser for the end-pumped Yb/sup 3+/:YAl/sub 3/(BO/sub 3/)/sub 4/ (Yb/sup 3+/:YAB) microchip is proposed. The effect of fluorescence concentration quenching (FCQ), the temperature distribution in the microchip medium, and then the refractive index distribution resulting from the thermal effect in the medium, the absorption of host, and the spatial distribution of SFD beam have been taken into account in the model. The calculated results are compared with those of experiments, and it reveals that this model is reasonable. It can be applied not only to the CW SFD laser of the Yb/sup 3+/:YAB microchip, but also to the quasi-three-level CW SFD laser of other microchips.