Amplified spontaneous emission model of thin disk laser with nonuniform temperature distribution

作者:Lin, Zhaocong; Zhu, Xiao; Zhu, Guangzhi*; Qiao, Yu; Wang, Mu; Zhao, Wenguang; Wang, Hailin; Qi, Lijun
来源:Journal of the Optical Society of America B-Optical Physics, 2017, 34(3): 625-632.
DOI:10.1364/JOSAB.34.000625

摘要

The amplified spontaneous emission (ASE) effect is a major factor affecting large size, high gain Yb:YAG thin disk lasers. In this paper, a model combining the rate equations including an ASE effect term and nonuniform temperature distribution in a thin disk crystal is presented. A numerical iterative method is used to analyze the dynamic behavior, the space distribution of ASE effect, and the optimum coupler reflectivity of the thin disk laser. It is shown that the temperature distribution and the size of the pump region are the main factors to influence the ASE effect and ultimately affect the output power and threshold of the laser system. In order to decrease the ASE effect, the coupler reflectivity can be adjusted to control the gain coefficient to increase output power.