Emission Enhancement Mechanisms in Dual-Pulse LIBS

摘要

In laser-induced breakdown spectroscopy (LIBS),a high-powered laser pulse (typically 100 mJ with a pulse width of several nanoseconds) is focused to a submillimeter spot on or in a solid,liquid,or gaseous sample.The result is a peak flux of 10~8-10~(10) W/cm~2 (1).Within tens to hundreds of picoseconds,free and loosely bound electrons interact with this intense electromagnetic field by absorbing energy from the temporally long nanosecond laser pulse through inverse bremsstrahlung processes;additional electrons are freed through collisions.