Transfer of the Species Dissolved in a Liquid into Laser Ablation Plasma: An Approach Using Emission Spectroscopy

We investigate the transfer of the dissolved species into the plasma during laser ablation in liquid. Laser ablation of a Cu target in LiCl + NaCl aqueous solutions and emission spectroscopy of the plasma are performed. Emission lines of Li and Na atoms are observed. Atomic density ratio <i>N</i>_Li/<i>N</i>_Na in the plasma estimated from the emission spectra agrees with the concentration ratio <i>C</i>_Li/<i>C</i>_Na in the solutions. This suggests the phase explosion of water due to the strong interaction between the extremely high-temperature matter ablated from the target and the surrounding water. This causes a cavitation bubble and the transfer of the dissolved species from the solution into the bubble without any element selectivity