摘要
为了研究固体激光器弛豫振荡的时间特性,针对高功率大口径Nd:YAG薄片激光器,从工作物质的能级结构和离子跃迁过程出发,采用四能级速率方程模型,综合考虑泵浦速率、损耗因子、温度等因素对激光器起振延迟时间的影响,建立了速率方程组,推导出激光起振延迟时间的数学表达式,模拟分析了泵浦速率、损耗因子、温度对激光起振延迟时间的影响。为验证理论分析结果,在kW级重复频率运行V型腔Nd:YAG薄片激光器上开展了实验研究。在泵浦电流分别为34,40,50,70 A时测量了反应谐振腔内光子数和反转粒子数变化的弛豫振荡曲线。并测量了在泵浦电流为30～80 A情况下的激光器起振延迟时间。实验结果表明起振延迟时间随泵浦速率的增加而减少,与理论分析结果一致。
Considering the four-level rate equations and the effects of pumping rate, loss factor and temperature, this paper theoretically deduced the expression of turn-on delay time for high power thin-disc laser. The numerical simulation results demon strate the relationship of the pumping rate, loss factor and temperature versus the turn-on delay time. Corresponding experimen tal research was carried out on a kW-level repetition-frequency V-cavity Nd：YAG thin-disc laser. The relaxation oscillation curves illustrating the variations of photon number and inverted population were measured. The turn-on delay time was measured when the pump current was in the range of 30 A to 80 A. The experiment results show that the turn-on delay time reduces with the in crease of pumping rate, which is consistent with the theoretical analysis.
出处
《强激光与粒子束》
EI
CAS
CSCD
北大核心
2013年第8期1883-1887,共5页
High Power Laser and Particle Beams
基金
国家自然科学基金项目(60890200)
国家自然科学基金委员会-中国工程物理研究院联合基金项目(10976017)
关键词
固体激光器
弛豫振荡
时间特性
速率方程
泵浦速率
solid-state lasers
relaxation oscillation
temporal characteristics
rate equation
pumping rate
