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Optical emission investigation of laser-produced MgB2 plume expanding in an Ar buffer gas

S. Amoruso·R. Bruzzese·N. Spinelli·R. Velotta·X. Wang·C. Ferdeghini
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Abstract

Optical emission spectroscopy is used to study the dynamics of the plasma generated by pulsed-laser irradiation of a MgB2 target, both in vacuum and at different Ar buffer gas pressures. The analysis of the time-resolved emission of selected species shows that the Ar background gas strongly influences the plasma dynamics. Above a fixed pressure, plasma propagation into Ar leads to the formation of blast waves causing both a considerable increase of the fraction of excited Mg atoms and a simultaneous reduction of their kinetic flux energy. These results can be particularly useful for optimizing MgB2 thin film deposition processes.

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S. Amoruso, R. Bruzzese, N. Spinelli, R. Velotta, X. Wang, C. Ferdeghini. 2002-04-17. Optical emission investigation of laser-produced MgB2 plume expanding in an Ar buffer gas. https://doi.org/10.1063/1.1484549

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