Femtosecond laser-induced breakdown spectroscopy of a preheated Cu target

Abstract

We present a study detailing femtosecond laser-induced breakdown spectroscopy (LIBS) of Cu with the sample preheated to different temperatures (22–120 °C). The detected spectral intensity of the plasma emission increased with the target temperature. Additionally, laser-induced plasma temperature was calculated by Boltzmann plot method. The plasma temperature rose along with the target temperature, indicating an enhanced interaction between the laser and the target in the case of a higher target temperature. We also simulated the thermal behavior of Cu irradiated by the femtosecond laser via a two-temperature model. As the sample temperature increased from 22 °C to 120 °C, the increase in the lattice temperature under femtosecond laser irradiation was approximately 200–300 K, and the ablated depth increased. The simulated results suggested that increasing the sample temperature led to an increase in the ablated mass. Based on this work, it can be seen that the method of preheating the ablation target can help enhance the spectral intensity and the detection sensitivity of femtosecond LIBS.