Plasmonic enhancement of high harmonic generation revisited: Predominance of atomic line emission

Abstract

We demonstrate nanostructure-enhanced extreme ultraviolet fluorescence from noble gases driven by low-energy, few-cycle light pulses. Despite sufficient local intensities, plasmon-enhanced high harmonic generation is not observed, which follows from the small, nanometer-size coherent source volume. © Owned by the authors, published by EDP Sciences, 2013.