Based on the model of cw end-pumped four-level system, the laser performances of Nd3+:YAG and Nd3+:YVO4 under indirect and direct pumping Nd3+ ions into the upper laser level are compared. The model takes the effect of concentration-dependent fluorescence quenching into account and enables the optimization of Nd3+ lasers. The slope efficiencies for incident and absorbed pumping powers as well as the incident and absorbed pumping thresholds of Nd3+:YAG and Nd3+:YVO4 lasers under indirect and direct pumping are analyzed. When the slope efficiency for the incident pumping power and the incident pumping threshold are concerned, a simple criterion determining which sample is suitable for direct pumping is given; however, in the case of the slope efficiency for the absorbed pumping power and the absorbed pumping threshold, the direct pumping is always better than the indirect pumping.
© 2005 Optical Society of America
Lasers and Laser Optics
Zhiyun Huang, Yidong Huang, Yujin Chen, and Zundu Luo, "Theoretical study on the laser performances of Nd3+:YAG and Nd3+:YVO4 under indirect and direct pumping," J. Opt. Soc. Am. B 22, 2564-2569 (2005)