低增益脉冲准分子激光阈值条件的研究

Study on the Low Gain Excimer Laser Optimum Transmission

对于激光系统性能而言,激光工作阈值条件具有非常重要的意义。低增益、宽带脉冲准分子激光的阈值条件和其激光泵浦脉冲有密切关系。在激光四能级系统速率方程的基础上,利用增益开关和Q开关的分析方法来研究低增益脉冲准分子激光阈值条件,给出了其在不同增益脉宽情况下一致的阈值条件。所得到的结论显示,在增益脉宽很短时,低增益准分子激光和连续激光的阈值条件完全不同,取决于时间积分增益系数要大于一临界值。

For the laser system performance, the threshold condition is of great significant.The threshold condition of low gain broadband-pulsed excimer laser is closely relative to the pump pulse .Based on the rate equations of four-level laser energy systems,the analytical methods of gain switching and Q-switch are used to study the threshold condition of the low gain pulsed excimer laser.The threshold conditions in the different gain duration are given.The analytical results show the threshold condition of low gain excimer laser is fundamentally different from the cw laser in short gain pulse,and depends on time integrated gain coefficient that has to exceed a critical value.