用2660(?)的紫外激光解离PbCl2分子时,发现在3740(?)和3734(?)波长上有较强的受激辐射输出.根据它们的光谱特性和铅原子的能级结构判断,这些辐射是基于双光子解离PbCl2分子得到的铅原子在6p~(23)P2亚稳能级上的布居而产生的光泵共振激光辐射和受激喇曼散射.提出了描述整个过程的理论模型,通过拟合实验结果,确定了2660(?)激光双光子解离PbCl2产生6p~(23)P2亚稳态铅原子的光解系数.当PbCl2分子密度为N(00)=6.21×10~(16)cm~(-3)时,光解产生的铅原子在6p~(23)P2和6p~(21)D2这两个亚稳态的最大布居数近似相等,称为2.0×10~(16)cm~(-3).

Strong stimulated radiations at wavelengths 3740 A have been observed when PbCl2 molecules are photodissociated by 2660 A ultraviolet laser. Dependences of these radiations on the pump laser intensity and PbCl2 molecular density have been studied experimentally. A theoretical model to describe these processes is put forward. These two raditions are identified as resonant laser radiation and stimulated Raman scattering originated from bhe population of the metastable level 6p23P2 of atomic Pb, which is produced by two-photon dissociation of PbCl. When molecular density of PbCl2 ig 6.21×l0 16cm-3, the maximum populations on the two metastable levels, 6p2 3P2 and 6p2 1D2 of atomic Pb are almost same, which equals 2.0×10 16 cm-3.