空气中激光烧蚀Cu产生等离子体发射光谱的研究

The research of laser induced Cu plasma emission spectra in air

利用Q-开关Nd:YAG激光器产生的1·06μm、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。采用不同的激光能量,分析了波长范围为440nm到540nm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104K以上,给出了靶面附近电子温度的空间演化规律,并探讨了N(Ⅱ)500·52nm谱线的谱线强度和半高全宽随激光能量的变化规律。

Using Nd. YAG laser （with a wavelength of 1064 nm and a pulse width of 10 ns） ablate copper target in air to observe the emission spectra of plasma. The space-resolved spectra are measured in the wavelength of 440 nm to 540 nm at the different 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 are obtained near the target, the strength and FWHM （the full width half maximum） of N（Ⅱ） 500.52 nm spectral line are analysed.