Research on temperature and electron density of iron alloy plasma induced by double pulse laser

Abstract

The plasma temperature and electron density is an important content of the research. It is useful for the study mechanism of laser induced breakdown. Two Nd:YAG pulse laser induce iron alloy formation plasma obtaining the 250~370nm spectrum diagram in the experiment. Double pulse spectra and single pulse spectra are compared, the electron density of double pulse is 2×10 17 cm -3 by Lorentz linear fitting; it is 0.3×10 17 cm -3 higher than single pulse. The plasma temperature of double pulse is 1.3×10 4 K by using Saha-Boltzmann multi line graph method. The advantages of double pulse laser are over single pulse comparing relationship between electron density and plasma temperature with delay time. Finally, the plasma in local thermal equilibrium based on the experimental results; plasma state meet the sufficient condition of calculation method.