Laser Pulse’s Frequency Effect on Plasma Parameters for Titanium Dioxide Produced by FHG of a Q-Switched ND: YAG Pulse Laser

Abstract

This work studies the relationship between laser irradiance and pulse frequency effect on plasma features of the TiO2. This target was irradiated by a Q-switched nanosecond Nd: YAG laser with the first harmonic generation (FHG) wavelength (1064[Formula: see text]nm), laser energy 500[Formula: see text]mJ, and pulse frequency ranging from 6[Formula: see text]Hz to 10[Formula: see text]Hz at atmospheric pressure. The Boltzmann plot and the Stark broadening methods calculated the plasma parameters ([Formula: see text] and [Formula: see text]. The findings were examined in light of the previously published experiments and theories, and it was discovered that they agreed with the hypothesis of the local thermodynamic equilibrium (LTE); on the other hand, research was conducted on the other basic plasma properties such as the Debye length ([Formula: see text]), the Debye sphere ([Formula: see text]), and the plasma frequency ([Formula: see text]). We observed that all plasma parameters are influenced by pulse frequency. The results clarify the linear change in electron temperature at increasing pulse frequency for TiO2 plasma. In contrast, the broadening of the line profiles related to electron density was evident with pulse frequency, causing an increase in electron density.