Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7674782 | Spectrochimica Acta Part B: Atomic Spectroscopy | 2014 | 5 Pages |
Abstract
The laser-induced plasma characteristics are strongly dependent on the surrounding pressure. Confining of the rapidly expanding plasma at low pressure conditions has shown that it is possible to perform the laser-induced breakdown spectroscopy (LIBS) detection by using a long gate width CCD detector. The acrylic window is placed above the sample for adjusting the plasma confining height for optimally extending the plasma persistence time. At 1Â mm confining height at 1Â torr, the signal intensity of Al III emission (452.8945Â nm) was enhanced up to 5.5 times the free expansion case. The signal intensity was markedly lower at 760Â torr as thickness of the window became larger, whereas it was constant at 1Â torr. It is suggested that optimum detection scheme as opposed to generation of strong plasma is more important in the low pressure LIBS study. The laser energy required for aluminum detection was only 3.664Â mJ/pulse at 1Â torr. The key aspect of this successful detection is the combined ablated mass confinement and the low pressure detection. This method has the potential to lead the detection of minor elements in metals at an increased sensitivity.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Soo Jin Choi, Kang-jae Lee, Jack J. Yoh,