Evaluation of analytical performance of double pulse laser-induced breakdown spectroscopy for the detection of rare earth elements

Abstract Double pulse laser-induced breakdown spectroscopy (DP-LIBS) in collinear configuration was demonstrated to enhance the signal intensity of three rare earth elements (REEs), Eu, Gd, Pr, and Y (Yttrium is included because of its similar chemical properties and occurrence in similar deposits as REE). Significant enhancement in spectral signals of all elements was observed with an aid of second laser. Two laser pulses of 1064 nm wavelength were employed in collinear geometry on the Pr2O3, Eu2O3, Gd2O3, and Y2O3 pellets to obtain emission spectra. For selected strong emission lines of Eu and Gd signal enhancement was found to be 3–7-fold and that for Y and Pr lines was observed to be 3–13-fold compared to single-pulse laser-induced breakdown spectroscopy (SP-LIBS). Role of inter-pulse delay between two pulses in DP-LIBS was found to be very crucial. While comparing selected ionic and neutral lines, ionic lines were found to have larger signal enhancement in DP-LIBS at the experimental conditions used in this study.