The Effect Of Nd³⁺ Doping On The LD-Pumped Nd: YAG Pulsed Laser Output Characteristics

Nd3+-doped laser is the most widely used lasers in scientific research, medical and industrial fields at the present. In this paper, the impact of Nd3+ doping concentration on the output characteristics of Nd:YAG laser at home and abroad was summarized and analyzed. To point out that the different concentration of Nd3+ doping causes the different pump light absorption capacity of laser crystal, different output efficiency, and the different threshold. It's one of the most important factor to impact the out characteristics. In some applications, to choose the best Nd3+ doping concentration can improve laser performance at a certain extent. The selection of the best Nd3+ doping concentration has a guiding sense for research and production of the solid-state laser.Nd:YAG laser crystal was an example in this paper, a comprehensive study about the impact of Nd3+ doping concentration on the output characteristics of Nd:YAG laser was did for the first time. The pumping uniformity of double -arched laser diode arrays side-pumped Nd:YAG laser was used to study the different doping concentration output characteristics of 1.0at.%,0.8at.%,0.6at.% of the Nd:YAG laser rods. Based on the theory of pump light distribution and four-level rate equation, the simulation results about fluorescence distribution of the Nd:YAG laser rods was given. The output laser energy, pulse width and the impact of thermal lens was calculated. Set up an experimental platform tostudy the impact of Nd3+ doping concentration on the of output characteristics Nd:YAG laser from the fluorescence distribution, the output laser energy, pulse width and laser setup time.Through the experimental research, in the case of thermal effect is not obvious, with the concentration of Nd3+ doping increasing, the output laser energy increase, pulse width becomes narrow, laser setup time becomes shorter. Quantitative relationship curves about Nd3+ doping concentration and laser setup time, laser output energy, pulse width and other parameters of the LD-pumped Nd:YAG laser was given. When the pump current was 100A, the output energy was 144mJ, and the pulse width was 7.6ns. The experimental results and the theoretical analysis results were basically consistent. The experimental results was an experimental basis for selection of the best Nd3+ doping concentration rod doped of LD-pumped pulsed Nd:YAG laser, it's also a reference to design and optimization of solid-state laser, with some reference value.