Open AccessCharacterization of laser-induced plasmas associated with energetic laser cleaning of metal particles on fused silica surfaces
Author(s) -
C. L. Harris,
Nan Shen,
Alexander M. Rubenchik,
Stavros G. Demos,
Manyalibo J. Matthews
Publication year - 2015
Publication title -
optics letters/optics index
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.524
H-Index - 272
eISSN - 1071-2763
pISSN - 0146-9592
DOI - 10.1364/ol.40.005212
Subject(s) - shadowgraphy , materials science , plasma , laser , laser ablation , atomic physics , plasma diagnostics , substrate (aquarium) , spectroscopy , laser induced breakdown spectroscopy , particle (ecology) , analytical chemistry (journal) , optics , chemistry , oceanography , physics , chromatography , quantum mechanics , geology
Time-resolved plasma emission spectroscopy was used to characterize the energy coupling and temperature rise associated with single, 10-ns pulsed laser ablation of metallic particles bound to transparent substrates. Plasma associated with Fe(I) emission lines originating from steel microspheres was observed to cool from >24,000 to ~15,000 K over ~220 ns as τ(-0.28), consistent with radiative losses and adiabatic gas expansion of a relatively free plasma. Simultaneous emission lines from Si(II) associated with the plasma etching of the SiO(2) substrate were observed yielding higher plasma temperatures, ~35,000 K, relative to the Fe(I) plasma. The difference in species temperatures is consistent with plasma confinement at the microsphere-substrate interface as the particle is ejected, and is directly visualized using pump-probe shadowgraphy as a function of pulsed laser energy.