从速率方程出发,采用在直流抽运上叠加脉冲抽运的方式,建立激光二极管(LD)抽运的增益开关型Nd:YVO4微片激光器的数学模型,并给出不同抽运条件下输出脉冲的时间特性。数值研究结果表明,当直流抽运速率、脉冲抽运速率和抽运脉宽的变化量在10%以内时,输出脉宽变化不大,而脉冲个数变化较大且与抽运参数呈非线性单调递增关系。利用建立的实验装置,测量了在不同激光二极管驱动电流和调制脉宽时输出脉冲的时间特性,发现驱动电流的增幅在10%以内时,输出脉宽变化小于5%,但输出脉冲个数增加较为明显,且实验结果与数值模拟结果相符。

Based on the rate equation, a mathematic model of laser diode (LD) pumped gain-switched Nd:YVO4 microchip laser under pre-pumping together with pulse pumping mechanism is presented. This model well shows the temporal characteristics of output pulses when the pumping parameters vary slightly. The results of numerical simulation indicate that the width of the output pulses changes little when the increase of pumping parameters is below 10%, however, the number of the output pulses increases rapidly and has a nonlinear monotone increasing relation with the pumping parameters. The experimental results of such gain-switched microchip laser are measured under the corresponding pumping conditions. It is found that the numerical and experimental results match with each other very well.