类镍氪32.8nm激光系统的增益特性理论研究

Theoretical Research on Characteristics of the Gains in Nickel-Like Krypton 32.8nm Laser System

为了研究类镍氪32.8nm激光输出所需的等离子体状态,利用Cowan程序计算了类镍氪32.8nm激光系统的有关原子参数。根据能级参数,建立并求解了准稳态近似下的有关能级速率方程,计算获得了激光上、下能级的相对粒子数密度和相对增益系数随电子温度和电子密度的变化规律,并分析了3d94p、3d94d和3d94f组态的能级对激光产生的影响。通过理论计算得到实现类镍氪32.8nm激光输出所需的最佳等离子体状态。最佳电子温度约为75eV,最佳电子密度约为1018 cm-3。计算结果为未来开展毛细管放电抽运类镍氪32.8nm激光实验提供了理论依据。

In order to study the plasma state for Ni-like Kr 32.8 nm laser,the atomic parameters of the Ni-like Kr 32.8 nm laser system are calculated with Cowan physical code.Based on the level parameters,the rate equations of energy level are established and solved under the quasi-steady-state approximation.The relative population density and the relative gain coefficient between the upper and lower levels of the laser are calculated with different electron temperatures and electron densities.The influence of the sub-levels of 3d^94p,3d^94d and 3d^94f configurations on laser generation is analyzed as well.The optimum plasma state for Ni-like Kr 32.8 nm laser generation is obtained through theoretical calculation.The best electron temperature is about 75 eV and the optimum electron density is about 10^18 cm^-3.These calculation results provide theoretical foundation for the experiment of Ni-like Kr 32.8 nm laser pumped by capillary discharge in the future.