Nanoparticle plasma ejected directly from solid copper by localized microwaves

Abstract

International audienceA plasma column ejected directly from solid copper by localized microwaves is studied. The effect stems from an induced hotspot that melts and emits ionized copper vapors as a confined fire column. Nanoparticles of ~20-120 nm size were revealed in the ejected column by in situ small-angle x-ray scattering. Optical spectroscopy confirmed the dominance of copper particles in the plasma column originating directly from the copper substrate. Nano- and macroparticles of copper were verified also by ex situ scanning electron microscopy. The direct conversion of solid metals to nanoparticles is demonstrated and various applications are proposed

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A photoelasticity approach for characterization of defects in microwave drilling of soda lime glass

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Observations of Ball-Lightning-Like Plasmoids Ejected from Silicon by Localized Microwaves

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