激光诱导Cu等离子体光谱的空间特性研究

The space characteristic research of laser induced Cu plasma spectra

利用Q -开关Nd :YAG激光器产生的 1.0 6 μm、10ns的脉冲激光聚焦在空气中的Cu靶上 ,观测了激光诱导的Cu等离子体发射光谱。采用激光能量为 4 5mJ/ pulse ,分析了波长范围为 4 4 0nm到 5 4 0nm的空间分辨发射光谱。在局部热力学平衡 (LTE)条件近似下 ,根据谱线的相对强度 ,得到了等离子体电子温度约在 10 4K以上 ,给出了靶面附近电子温度和谱线半高全宽的空间演化规律。

Using Nd:YAG laser (with a wavelength of 1064nm and a pulse width of 10ns) ablate copper target in air to observe the emission spectra of plasma. The space-resolved spectra are measured in the wavelength of 440nm to 540nm at the 45mJ/pulse of laser energy. Under the model of local thermodynamic equilibrium, the electronic temperature of Cu plasma are deduced to be in the 104 scale by the relative line intensities. Finally, space characteristics of electron temperature and FWHM are obtained near the target. We found they decrease at different expontents with the increment of distance of target.