Correlation of characteristic signals of laser-induced plasmas

Abstract

Complementary methods are introduced to laser-induced breakdown spectroscopy measurement systems in order to provide complete information about the investigated sample, phenomena beyond laser-matter interaction and evolution of laser-induced plasmas and its properties. Another use of such complementary signals is in their potential use for signal standardization. So far one additional method is used at a time to achieve this goal, be it direct imaging of the plasma, shadowgraphy method, measurement of the sound signal or energy of the laser pulse. In this work we were able to record all above mentioned data at the same time as the LIBS spectra or even energy of the individual laser pulses. This allowed us to observe correlation between all the data with optical emission signal of laser induced plasmas. Each data pair is represented by correlation coefficient, where the average value of correlation coefficients R2 is 0.87. After correcting the data with the energy of laser pulse and optical emission signal, we achieved average value of the correlation coefficients R2 0.98.