The influence of the target temperature on the molecular emission of femtosecond laser-induced breakdown spectroscopy (LIBS) was investigated experimentally. An Al target was ablated to produce laser-induced plasma. The Al target was uniformly heated to a maximum of 250 C. The measured molecular emission was AlO (Δν=0) from the femtosecond LIBS of the Al target. The measurements indicated that the molecular emission of AlO increased as the temperature of the Al target increased. In addition, a two-temperature model was used to simulate the evolution of the electron and lattice temperature of the Al target with different initial temperatures. The simulated results showed that the electron and lattice temperatures of Al irradiated by the femtosecond laser increased as the initial temperature of the Al target increased; also, the simulated ablated depth increased. Therefore, an increase in the initial Al target temperature resulted in an enhancement in the spectral signal of AlO from the femtosecond LIBS of Al, which was directly related to the increase in the size of the ablated crater. The study suggested that increasing the temperature of the target improves the intensity of molecular emission in femtosecond LIBS.

实验研究了目标温度对飞秒激光诱导击穿光谱（LIBS）分子发射的影响。烧蚀Al靶以产生激光诱导的等离子体。将Al靶均匀加热至最高250°C。测得的分子发射为AlO（Δν= 0）从Al目标的飞秒LIBS。测量结果表明，AlO的分子发射随Al靶标温度的升高而增加。另外，使用两个温度模型来模拟具有不同初始温度的Al靶材的电子和晶格温度的演变。模拟结果表明，飞秒激光辐照的Al的电子和晶格温度随Al靶的初始温度的升高而升高。同样，模拟的烧蚀深度也增加了。因此，初始Al目标温度的升高导致来自Al的飞秒LIBS的AlO的光谱信号的增强，这与烧蚀的弹坑的尺寸的增加直接相关。