样品温度对激光诱导黄铜等离子体辐射特性的影响

为了研究样品温度变化对激光诱导铜等离子体特征参数的影响,利用单脉冲激光诱导激发加热台上的样品形成等离子体,改变样品温度获得相应的黄铜等离子体发射光谱。分析了样品温度变化时特征谱线强度的变化,并在局部热平衡(Local thermodynamic equilibrium, LTE)条件下,利用Boltzman方程和Stark展宽计算并获得不同样品温度条件下等离子体电子温度和电子密度随时间的演化规律,同时讨论了激光诱导金属等离子体光谱增强的原因。实验结果表明,延迟时间相同时,样品温度越高,谱线强度越强,电子温度和电子密度越大。由此可见,适当升高样品温度可以提高谱线强度。

Effect of Sample Temperature on Radiation Characteristics of Laser-Induced Cu Plasma

In order to study the effect of sample temperature on the characteristic parameters of laser-induced copper plasma,Cu sample on heating stage was excited by a single pulse laser to form plasma, and the corresponding plasmaemission spectra of brass were obtained by changing the sample temperature. The intensity change of thecharacteristic spectral line corresponding to the change of sample temperature was analyzed, and theevolution rule of electron temperature and electron density with time at different sample temperaturesare obtained by using Boltzmann equation and Stark broadening under the assumption of local thermodynamicequilibrium (LTE). At the same time, the cause of the radiation enhancement of laser-induced metalplasma was also discussed. The results showed that, given the same delay time, the higher the sampletemperature is, the stronger the spectral intensity is, and the higher the electrontemperature and electron density are. It is indicated that the resulting spectral intensitycan be increased by increasing the sample temperature appropriately.