半导体抽运铯蒸气激光器阈值特性分析

摘要

本文建立了一种速率方程模型，以铯蒸气为例描述了半导体抽运碱金属蒸气激光器的阈值特性。经数值求解该模型，定量分析了抽运光束腰位置和半径、蒸气池长度、运行温度等参量对激光器的阈值抽运功率的影响。结果表明，存在最佳的抽运光束腰位置和半径、蒸气池长度以及运行温度使阈值最低，此外改善抽运光束质量也能有效降低阈值抽运功率。所得规律与目前实验事实基本相符，表明了该模型能较好地反映半导体抽运碱金属蒸气激光器的阈值特性，为该类激光器的优化设计提供一定的借鉴和参考。%A rate equation model is established to describe the threshold characteristics of a diode-pumped Cs vapor laser in this paper. With the help of the numerical solution for the model, the influences of several parameters (waist position and waist radius of pump laser, length of vapor cell, and operating temperature) on the threshold pump power are analyzed. Results show that there are optimal values of the pump waist position and radius, vapor cell length and operating temperature to ensure a lowest threshold pump power. Besides, the decrease of divergence angle can reduce threshold pump power effectively. Simulation results are in good agreement with the experimental data. It is shown that the model can be used to reveal the threshold characteristics of diode-pumped alkali vapor laser and may serve as a theoretical guidance for the optimization design of this laser.