纵向抽运准三能级连续激光器的抽运吸收饱和效应  

Pump Absorption Saturation Effects in Longitudinally-Pumped Quasi-Three-Level Continuous-Wave Lasers

作　　者：廖雄勇[1] 黄朝红[1] 许惠英[1] 蔡志平[1] 

机构地区：[1]厦门大学电子工程系,福建厦门361005

出　　处：《中国激光》2010年第9期2355-2360,共6页Chinese Journal of Lasers

基　　金：福建省青年科技创新基金(2007F3100)资助课题

摘　　要：基于速率方程和腔内光传输方程,推导了纵向抽运准三能级连续激光器的抽运吸收效率、斜率效率、腔内基波几何平均光强、激光阈值、激光输出光强和功率的显式解析表达式。讨论了抽运吸收饱和效应对抽运吸收效率、激光阈值、激光转换效率和腔内基波几何平均光强的影响。理论分析和数值模拟表明,抽运饱和效应对激光性能的影响与抽运吸收截面和激光发射截面的比值、平均单程损耗因子、抽运能级与激光上下能级的粒子数布居因子及晶体长度等因素有关。当晶体越短、抽运吸收截面和激光发射截面的比值越大、腔损耗越大时,抽运吸收饱和效应越明显。抽运吸收效率的下降会导致激光阈值升高、腔内基波几何平均光强以及激光转换效率的下降。The explicit analytical expressions of pump absorption efficiency,slope efficiency,fundamental-wave geometric average intensity in cavity,laser threshold,output laser intensity and power for longitudinally-pumped quasi-three-level continuous-wave lasers have been derived using the rate equations and optical transmission equations in cavity.Furthermore,the influences of laser-induced pump absorption saturation effect on pump absorption efficiency,laser threshold,conversion efficiency and fundamental-wave geometric average intensity in cavity are discussed.Theoretical analysis and numerical simulations indicate that the influences of the pump absorption saturation on the performance of lasers relate to the ratio of the pump absorption cross section and laser stimulated emission cross section,the average single-pass loss factor,the population factors of pump energy level and upper and lower laser energy levels,length of laser crystal,etc.When the laser crystal is shorter,the average single-pass loss factor is larger,the ratio of pump absorption cross section and laser stimulated emission cross section is larger,and the pump absorption saturation effect is more obvious.The decline of the pump absorption efficiency results in the increase of the laser threshold and the decrease of the fundamental-wave geometric average intensity in cavity and laser conversion efficiency.

关 键 词：激光器 准三能级 抽运吸收饱和 纵向抽运 平均单程损耗因子 

分 类 号：TN248.1[电子电信—物理电子学]