Plasma condensation effect induced by ambient pressure in laser-induced breakdown spectroscopy

Laser-induced breakdown spectroscopy (LIBS) is a promising technique for in situ chemical analysis in ocean observation. Extensive experimental investigations were carried out to understand the plasma-ambient pressure interaction mechanism in a liquid environment. Results shows that plasma temperature and electron density increase with increasing pressure. Under elevated pressure conditions, the electron density increases at the late plasma stage. The results indicate that plasma could be condensed, which leads to an increase in plasma temperature and electron density. (C) 2014 The Japan Society of Applied Physics