The pumping threshold is an important parameter for laser sources. Limited by the intricate transition mechanism of the one-color two-photon excitation, there has been a shortage of theoretical studies on the pumping threshold characteristics of alkali vapors. Thus, we propose a physical model of the pumping threshold by innovatively combining the coupled wave equation and the rate equation for one-color two-photon excited Cs vapor. To verify the validity of the model, we compare our simulation results with the available experimental data and show that they agree well with each other. By analyzing the main factors influencing the pumping threshold, we find that the cell temperature and frequency detuning of the pumping laser have a decisive impact on the pumping threshold. These results can provide a valuable reference for the selection of appropriate pumping parameters in further experiments.

中文翻译：

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单色双光子激发Cs蒸气泵浦阈值特性的建模与分析

泵浦阈值是激光源的一个重要参数。受限于单色双光子激发的复杂跃迁机制，碱蒸气泵浦阈值特性的理论研究一直缺乏。因此，我们通过创新地结合耦合波动方程和单色双光子激发 Cs 蒸气的速率方程，提出了泵浦阈值的物理模型。为了验证模型的有效性，我们将我们的模拟结果与可用的实验数据进行了比较，并表明它们相互吻合。通过分析影响泵浦阈值的主要因素，我们发现泵浦激光器的电池温度和频率失谐对泵浦阈值有决定性影响。