样品温度和空间约束两种方法相结合对激光诱导击穿光谱的影响

升高样品温度和采用空间约束能提高激光诱导击穿光谱的信号强度,两种技术的结合可以进一步提高激光诱导击穿光谱的光谱强度.本文在空气环境中研究了升高样品温度和空间约束效应两种方法相结合对激光诱导击穿光谱的影响,测量了激光诱导铝等离子体的时间分辨光谱.实验结果表明:升高样品温度能增加激光诱导击穿光谱的信号强度,高温样品能耦合更...

Effects of the combination of sample temperature and spatial confinement on laser-induced breakdown spectroscopy

The signal intensity of Laser-Induced Breakdown Spectroscopy(LIBS)can be improved by increasing sample temperature and confining space confinement.The combination of the two techniques can further improve the spectral intensity of LIBS.In this paper,the effects of increasing a sample’s temperature and spatial confinement on LIBS are studied in air,and the time-resolved spectra of laser-induced aluminum plasma are measured.The experimental results show that increasing the sample’s temperature can increase the signal intensity of LIBS since a sample with a higher temperature can absorb more laser energy;when the cylindrical cavity is used to confine the plasma,the spectral emission is further improved.The effect of the combination of the two experimental conditions is that the signal intensity of LIBS is significantly stronger than that of either condition alone.The intensity of Al(I)396.2 nm increases to 1.4 times at 200°C with higher temperature conditions alone,1.3 times when spatial confinement is applied alone,and 2.1 times at 200°C with spatial confinement.The emission intensity with the combined effects is higher than the sum of that under the two individual conditions.The effect of the combination is mainly based on the fact that laser irradiation of the sample under a higher temperature generates stronger shock waves that can more effectively compress a larger-sized plasma plume,thereby further improving the spectral intensity of LIBS.